diff --git a/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/llama_index/postprocessor/voyageai_rerank/base.py b/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/llama_index/postprocessor/voyageai_rerank/base.py
index 7a6cf670b39f0..5ef168e7af68b 100644
--- a/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/llama_index/postprocessor/voyageai_rerank/base.py
+++ b/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/llama_index/postprocessor/voyageai_rerank/base.py
@@ -15,11 +15,13 @@
 
 class VoyageAIRerank(BaseNodePostprocessor):
     model: str = Field(description="Name of the model to use.")
-    top_n: int = Field(
-        description="The number of most relevant documents to return. If not specified, the reranking results of all documents will be returned."
+    top_n: Optional[int] = Field(
+        description="The number of most relevant documents to return. If not specified, the reranking results of all documents will be returned.",
+        default=None,
     )
     truncation: bool = Field(
-        description="Whether to truncate the input to satisfy the 'context length limit' on the query and the documents."
+        description="Whether to truncate the input to satisfy the 'context length limit' on the query and the documents.",
+        default=True,
     )
 
     _client: Any = PrivateAttr()
@@ -29,7 +31,7 @@ def __init__(
         model: str,
         api_key: Optional[str] = None,
         top_n: Optional[int] = None,
-        truncation: Optional[bool] = None,
+        truncation: bool = True,
         # deprecated
         top_k: Optional[int] = None,
     ):
@@ -55,7 +57,10 @@ def _postprocess_nodes(
     ) -> List[NodeWithScore]:
         dispatcher.event(
             ReRankStartEvent(
-                query=query_bundle, nodes=nodes, top_n=self.top_n, model_name=self.model
+                query=query_bundle,
+                nodes=nodes,
+                top_n=self.top_n or len(nodes),
+                model_name=self.model,
             )
         )
 
@@ -70,7 +75,7 @@ def _postprocess_nodes(
                 EventPayload.NODES: nodes,
                 EventPayload.MODEL_NAME: self.model,
                 EventPayload.QUERY_STR: query_bundle.query_str,
-                EventPayload.TOP_K: self.top_n,
+                EventPayload.TOP_K: self.top_n or len(nodes),
             },
         ) as event:
             texts = [
diff --git a/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/pyproject.toml b/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/pyproject.toml
index d15dd97efe8f9..7d48f7a7de7ae 100644
--- a/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/pyproject.toml
+++ b/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/pyproject.toml
@@ -30,7 +30,7 @@ license = "MIT"
 name = "llama-index-postprocessor-voyageai-rerank"
 packages = [{include = "llama_index/"}]
 readme = "README.md"
-version = "0.3.1"
+version = "0.3.2"
 
 [tool.poetry.dependencies]
 python = ">=3.9,<4.0"
diff --git a/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/tests/test_postprocessor_voyageai-rerank.py b/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/tests/test_postprocessor_voyageai-rerank.py
index 48e221a6bf5dc..e339f17de5eeb 100644
--- a/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/tests/test_postprocessor_voyageai-rerank.py
+++ b/llama-index-integrations/postprocessor/llama-index-postprocessor-voyageai-rerank/tests/test_postprocessor_voyageai-rerank.py
@@ -1,10 +1,13 @@
-from llama_index.core.postprocessor.types import BaseNodePostprocessor
-from llama_index.core.schema import NodeWithScore, QueryBundle, TextNode
+import os
+
+import pytest
+from pytest_mock import MockerFixture
 from voyageai.api_resources import VoyageResponse
+from voyageai.object.reranking import RerankingObject
 
+from llama_index.core.postprocessor.types import BaseNodePostprocessor
+from llama_index.core.schema import NodeWithScore, QueryBundle, TextNode
 from llama_index.postprocessor.voyageai_rerank import VoyageAIRerank
-from voyageai.object.reranking import RerankingObject
-from pytest_mock import MockerFixture
 
 rerank_sample_response = {
     "object": "list",
@@ -22,7 +25,11 @@ def test_class():
     assert BaseNodePostprocessor.__name__ in names_of_base_classes
 
 
-def test_rerank(mocker: MockerFixture) -> None:
+@pytest.mark.parametrize(
+    "constructor_kwargs",
+    [{"top_n": 2, "truncation": True}, {"top_n": None}],
+)
+def test_rerank(mocker: MockerFixture, constructor_kwargs: dict) -> None:
     # Mocked client with the desired behavior for embed_documents
     result_object = RerankingObject(
         documents=["0", "1"],
@@ -39,7 +46,7 @@ def test_rerank(mocker: MockerFixture) -> None:
     )
 
     voyageai_rerank = VoyageAIRerank(
-        api_key="api_key", top_n=2, model="rerank-lite-1", truncation=True
+        api_key="api_key", model="rerank-lite-1", **constructor_kwargs
     )
     result = voyageai_rerank.postprocess_nodes(
         nodes=[
@@ -51,3 +58,20 @@ def test_rerank(mocker: MockerFixture) -> None:
     assert len(result) == 2
     assert result[0].text == "text2"
     assert result[1].text == "text1"
+
+
+def test_rerank_construction_with_no_optional_kwargs():
+    os.environ["VOYAGE_API_KEY"] = "mock_api_key"
+    reranker = VoyageAIRerank(model="rerank-2")
+    assert reranker.truncation
+    assert reranker.top_n is None
+    assert reranker.model == "rerank-2"
+
+
+def test_rerank_construction_with_optional_kwargs():
+    reranker = VoyageAIRerank(
+        model="rerank-2", api_key="mock_api_key", top_n=10, truncation=False
+    )
+    assert not reranker.truncation
+    assert reranker.top_n == 10
+    assert reranker.model == "rerank-2"