diff --git a/packages/accel-record-core/src/relation/where.ts b/packages/accel-record-core/src/relation/where.ts
index 3152d1b3..2ba9fb61 100644
--- a/packages/accel-record-core/src/relation/where.ts
+++ b/packages/accel-record-core/src/relation/where.ts
@@ -41,8 +41,16 @@ export class Where {
     const newOptions = JSON.parse(JSON.stringify(this.options));
     for (const key in input) {
       const column = this.model.attributeToColumn(key);
-      if (!column) throw new Error(`Attribute not found: ${key}`);
-      if (Array.isArray(input[key])) {
+      if (!column) {
+        const associationWheres = this.getAssocationWhere(key, input[key]);
+        if (associationWheres) {
+          for (const where of associationWheres) {
+            newOptions["wheres"].push(where);
+          }
+        } else {
+          throw new Error(`Attribute not found: ${key}`);
+        }
+      } else if (Array.isArray(input[key])) {
         newOptions["wheres"].push([column, "in", input[key]]);
       } else if (input[key] != null && typeof input[key] === "object") {
         for (const operator in input[key]) {
@@ -59,6 +67,35 @@ export class Where {
     return new Relation(this.model, newOptions);
   }
 
+  private getAssocationWhere<T, M extends ModelMeta>(
+    this: Relation<T, M>,
+    key: Extract<keyof M["WhereInput"], string>,
+    value: any,
+    op: string = "in"
+  ) {
+    const field = this.model.findField(key);
+    if (field?.relationName == undefined) return;
+
+    const where: any = {};
+
+    const records = [value].flat();
+    for (let i = 0; i < field.foreignKeys.length; i++) {
+      const column = this.model.attributeToColumn(field.foreignKeys[i]);
+      if (!column) return;
+      where[column] ||= [];
+
+      for (const record of records) {
+        where[column].push(record[field.primaryKeys[i]]);
+      }
+    }
+
+    return Object.entries(where).map(([column, values]) => [
+      column,
+      op,
+      values,
+    ]);
+  }
+
   /**
    * Adds a "where not" condition to the current relation.
    *
@@ -72,8 +109,20 @@ export class Where {
     const newOptions = JSON.parse(JSON.stringify(this.options));
     for (const key in input) {
       const column = this.model.attributeToColumn(key);
-      if (!column) throw new Error(`Attribute not found: ${key}`);
-      if (input[key] != null && typeof input[key] === "object") {
+      if (!column) {
+        const associationWheres = this.getAssocationWhere(
+          key,
+          input[key],
+          "not in"
+        );
+        if (associationWheres) {
+          for (const where of associationWheres) {
+            newOptions["wheres"].push(where);
+          }
+        } else {
+          throw new Error(`Attribute not found: ${key}`);
+        }
+      } else if (input[key] != null && typeof input[key] === "object") {
         for (const operator in input[key]) {
           if (operator === "in") {
             newOptions["wheres"].push([column, "not in", input[key][operator]]);
diff --git a/packages/prisma-generator-accel-record/src/generators/type.ts b/packages/prisma-generator-accel-record/src/generators/type.ts
index 3c81fd3a..7e1f5276 100644
--- a/packages/prisma-generator-accel-record/src/generators/type.ts
+++ b/packages/prisma-generator-accel-record/src/generators/type.ts
@@ -161,18 +161,6 @@ declare module "accel-record" {
         return ` & ({ ${f.name}: ${f.type} } | { ${foreignKeys} })`;
       })
       .join("");
-    const whereInputs =
-      model.fields
-        .filter(reject)
-        .filter(
-          (field) => field.relationName == undefined && field.type != "Json"
-        )
-        .map((field) => {
-          const type = field.typeName;
-          const filter = getFilterType(type);
-          return `\n    ${field.name}?: ${type} | ${type}[] | ${filter} | null;`;
-        })
-        .join("") + "\n  ";
     const orderInputs =
       model.fields
         .filter(reject)
@@ -197,7 +185,7 @@ type ${model.meta} = {
   CreateInput: {
 ${columns}
   }${associationColumns};
-  WhereInput: {${whereInputs}};
+  WhereInput: {${whereInputs(model)}};
   OrderInput: {${orderInputs}};
 };
 registerModel(${model.persistedModel});
@@ -297,3 +285,22 @@ const columnDefines = (model: ModelWrapper) =>
       };`;
     })
     .join("\n");
+
+const whereInputs = (model: ModelWrapper) =>
+  model.fields
+    .filter(
+      (field) =>
+        field.relationName == undefined ||
+        (field.relationFromFields?.length ?? 0) > 0
+    )
+    .filter((field) => field.type != "Json")
+    .map((field) => {
+      const type = field.typeName;
+      const filter = getFilterType(type);
+      if (field.relationName) {
+        if (field.name == "posts") console.log(field);
+        return `\n    ${field.name}?: ${field.type} | ${field.type}[];`;
+      }
+      return `\n    ${field.name}?: ${type} | ${type}[] | ${filter} | null;`;
+    })
+    .join("") + "\n  ";
diff --git a/tests/models/_types.ts b/tests/models/_types.ts
index 81f2fde6..58a18f1a 100644
--- a/tests/models/_types.ts
+++ b/tests/models/_types.ts
@@ -185,7 +185,9 @@ type UserTeamMeta = {
     assignedBy: string;
   } & ({ user: User } | { userId: number }) & ({ team: Team } | { teamId: number });
   WhereInput: {
+    user?: User | User[];
     userId?: number | number[] | Filter<number> | null;
+    team?: Team | Team[];
     teamId?: number | number[] | Filter<number> | null;
     assignedAt?: Date | Date[] | Filter<Date> | null;
     assignedBy?: string | string[] | StringFilter | null;
@@ -239,6 +241,7 @@ type PostMeta = {
     title?: string | string[] | StringFilter | null;
     content?: string | string[] | StringFilter | null;
     published?: boolean | boolean[] | undefined | null;
+    author?: User | User[];
     authorId?: number | number[] | Filter<number> | null;
   };
   OrderInput: {
@@ -321,6 +324,7 @@ type SettingMeta = {
   } & ({ user: User } | { userId: number });
   WhereInput: {
     settingId?: number | number[] | Filter<number> | null;
+    user?: User | User[];
     userId?: number | number[] | Filter<number> | null;
     threshold?: number | number[] | Filter<number> | null;
     createdAt?: Date | Date[] | Filter<Date> | null;
@@ -372,6 +376,7 @@ type ProfileMeta = {
   } & ({ user: User } | { userId: number });
   WhereInput: {
     id?: number | number[] | Filter<number> | null;
+    user?: User | User[];
     userId?: number | number[] | Filter<number> | null;
     bio?: string | string[] | StringFilter | null;
     point?: number | number[] | Filter<number> | null;
@@ -461,6 +466,7 @@ type EmployeeMeta = {
     id?: number | number[] | Filter<number> | null;
     name?: string | string[] | StringFilter | null;
     companyId?: number | number[] | Filter<number> | null;
+    company?: Company | Company[];
   };
   OrderInput: {
     id?: SortOrder;
diff --git a/tests/models/relation.test.ts b/tests/models/relation.test.ts
index b7bf6b2e..85c1f875 100644
--- a/tests/models/relation.test.ts
+++ b/tests/models/relation.test.ts
@@ -134,6 +134,15 @@ describe("Relation", () => {
     ).toHaveLength(2);
   });
 
+  test("#where() with association", () => {
+    const users = $user.createList(2);
+    $post.createList(2, { author: users[0] });
+    $post.createList(1, { author: users[1] });
+    expect(Post.all().where({ author: users[0] }).count()).toBe(2);
+    expect(Post.all().where({ author: users }).count()).toBe(3);
+    expect(Post.all().where({ author: [] }).count()).toBe(0);
+  });
+
   test("#whereNot()", () => {
     $user.create({ name: "hoge", age: 20 });
     $user.create({ name: "fuga", age: 30 });
@@ -152,6 +161,15 @@ describe("Relation", () => {
     expect(User.all().whereNot({ age: null }).first()?.name).toBe("hoge");
   });
 
+  test("#whereNot() with association", () => {
+    const users = $user.createList(2);
+    $post.createList(2, { author: users[0] });
+    $post.createList(1, { author: users[1] });
+    expect(Post.all().whereNot({ author: users[0] }).count()).toBe(1);
+    expect(Post.all().whereNot({ author: users }).count()).toBe(0);
+    expect(Post.all().whereNot({ author: [] }).count()).toBe(3);
+  });
+
   test("#whereRaw()", () => {
     $user.create({ name: "hoge", age: 20 });
     $user.create({ name: "fuga", age: 30 });