diff --git a/RELEASE.md b/RELEASE.md
index 9b70726658..3908db36d8 100644
--- a/RELEASE.md
+++ b/RELEASE.md
@@ -9,6 +9,7 @@ Please follow the established format:
 
 ## Bug fixes and other changes
 
+- Add support for fastapi >= 0.100.0 (#1529)
 - Fix dataset factory patterns in Experiment Tracking. (#1588)
 
 # Release 6.6.1
diff --git a/package/features/steps/lower_requirements.txt b/package/features/steps/lower_requirements.txt
index 317309a4c2..c8cf3c5225 100644
--- a/package/features/steps/lower_requirements.txt
+++ b/package/features/steps/lower_requirements.txt
@@ -1,5 +1,5 @@
 ipython==7.0.0
-fastapi==0.73.0
+fastapi==0.100.0
 fsspec==2021.4
 aiofiles==22.1.0
 uvicorn[standard]==0.22.0
diff --git a/package/kedro_viz/api/rest/responses.py b/package/kedro_viz/api/rest/responses.py
index bb49e919cb..e7c6993fdb 100644
--- a/package/kedro_viz/api/rest/responses.py
+++ b/package/kedro_viz/api/rest/responses.py
@@ -2,7 +2,7 @@
 # pylint: disable=missing-class-docstring,too-few-public-methods,invalid-name
 import abc
 import logging
-from typing import Any, Dict, List, Optional, Union
+from typing import TYPE_CHECKING, Any, Dict, List, Optional, Union
 
 import fsspec
 import orjson
@@ -10,7 +10,6 @@
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import JSONResponse, ORJSONResponse
 from kedro.io.core import get_protocol_and_path
-from pydantic import BaseModel
 
 from kedro_viz.api.rest.utils import get_package_version
 from kedro_viz.data_access import data_access_manager
@@ -24,6 +23,16 @@
     TranscodedDataNodeMetadata,
 )
 
+if TYPE_CHECKING:
+    from pydantic import BaseModel
+else:
+    try:
+        # Triggered if pydantic v2 is installed
+        from pydantic.v1 import BaseModel
+    except ImportError:
+        # Triggered if pydantic v1 is installed
+        from pydantic import BaseModel
+
 logger = logging.getLogger(__name__)
 
 _FSSPEC_PACKAGE_NAME = "fsspec"
@@ -47,7 +56,7 @@ class BaseGraphNodeAPIResponse(BaseAPIResponse):
     type: str
 
     # If a node is a ModularPipeline node, this value will be None, hence Optional.
-    modular_pipelines: Optional[List[str]]
+    modular_pipelines: Optional[List[str]] = None
 
 
 class TaskNodeAPIResponse(BaseGraphNodeAPIResponse):
@@ -81,9 +90,9 @@ class Config:
 
 
 class DataNodeAPIResponse(BaseGraphNodeAPIResponse):
-    layer: Optional[str]
-    dataset_type: Optional[str]
-    stats: Optional[Dict]
+    layer: Optional[str] = None
+    dataset_type: Optional[str] = None
+    stats: Optional[Dict] = None
 
     class Config:
         schema_extra = {
@@ -108,12 +117,12 @@ class Config:
 
 
 class TaskNodeMetadataAPIResponse(BaseAPIResponse):
-    code: Optional[str]
-    filepath: Optional[str]
-    parameters: Optional[Dict]
+    code: Optional[str] = None
+    filepath: Optional[str] = None
+    parameters: Optional[Dict] = None
     inputs: List[str]
     outputs: List[str]
-    run_command: Optional[str]
+    run_command: Optional[str] = None
 
     class Config:
         schema_extra = {
@@ -129,14 +138,14 @@ class Config:
 
 
 class DataNodeMetadataAPIResponse(BaseAPIResponse):
-    filepath: Optional[str]
+    filepath: Optional[str] = None
     type: str
-    plot: Optional[Dict]
-    image: Optional[str]
-    tracking_data: Optional[Dict]
-    run_command: Optional[str]
-    preview: Optional[Dict]
-    stats: Optional[Dict]
+    plot: Optional[Dict] = None
+    image: Optional[str] = None
+    tracking_data: Optional[Dict] = None
+    run_command: Optional[str] = None
+    preview: Optional[Dict] = None
+    stats: Optional[Dict] = None
 
     class Config:
         schema_extra = {
@@ -152,8 +161,8 @@ class TranscodedDataNodeMetadataAPIReponse(BaseAPIResponse):
     filepath: str
     original_type: str
     transcoded_types: List[str]
-    run_command: Optional[str]
-    stats: Optional[Dict]
+    run_command: Optional[str] = None
+    stats: Optional[Dict] = None
 
 
 class ParametersNodeMetadataAPIResponse(BaseAPIResponse):
@@ -199,7 +208,7 @@ class NamedEntityAPIResponse(BaseAPIResponse):
     """
 
     id: str
-    name: Optional[str]
+    name: Optional[str] = None
 
 
 class ModularPipelineChildAPIResponse(BaseAPIResponse):
diff --git a/package/requirements.txt b/package/requirements.txt
index b3d2b9cd36..294f4ef325 100644
--- a/package/requirements.txt
+++ b/package/requirements.txt
@@ -1,9 +1,9 @@
 packaging~=23.0
 kedro>=0.17.5
 ipython>=7.0.0, <9.0
-fastapi>=0.73.0, <0.96.0
-fsspec[s3]>=2021.4, <2024.1 
-aiofiles>=22.1.0
+fastapi>=0.100.0,<0.102.0
+fsspec[s3]>=2021.4, <2024.1
+aiofiles==22.1.0
 uvicorn[standard]~=0.22.0
 watchgod~=0.8.2
 plotly>=4.0
diff --git a/package/test_requirements.txt b/package/test_requirements.txt
index e9b39a7950..52a1cabc1b 100644
--- a/package/test_requirements.txt
+++ b/package/test_requirements.txt
@@ -8,7 +8,7 @@ behave~=1.2
 black~=23.3
 boto3~=1.26
 flake8~=5.0
-fastapi[all]>=0.73.0, <0.96.0
+fastapi[all]>=0.73.0, <0.104.0
 isort~=5.11
 matplotlib~=3.5
 mypy~=1.0