diff --git a/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.cpp b/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.cpp
index 4f0e28c07c35d0b04b8f976f7a39cead1ffb345d..b2110df952b63313a6e75138d698c95351654920 100644
--- a/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.cpp
+++ b/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.cpp
@@ -27,7 +27,8 @@
 namespace zilliz {
 namespace knowhere {
 
-IndexModelPtr IVFSQHybrid::Train(const DatasetPtr &dataset, const Config &config) {
+IndexModelPtr
+IVFSQHybrid::Train(const DatasetPtr &dataset, const Config &config) {
     auto build_cfg = std::dynamic_pointer_cast<IVFSQCfg>(config);
     if (build_cfg != nullptr) {
         build_cfg->CheckValid(); // throw exception
@@ -58,7 +59,8 @@ IndexModelPtr IVFSQHybrid::Train(const DatasetPtr &dataset, const Config &config
     }
 }
 
-VectorIndexPtr IVFSQHybrid::CopyGpuToCpu(const Config &config) {
+VectorIndexPtr
+IVFSQHybrid::CopyGpuToCpu(const Config &config) {
     std::lock_guard<std::mutex> lk(mutex_);
 
     if (auto device_idx = std::dynamic_pointer_cast<faiss::gpu::GpuIndexIVF>(index_)) {
@@ -74,7 +76,8 @@ VectorIndexPtr IVFSQHybrid::CopyGpuToCpu(const Config &config) {
     }
 }
 
-VectorIndexPtr IVFSQHybrid::CopyCpuToGpu(const int64_t &device_id, const Config &config) {
+VectorIndexPtr
+IVFSQHybrid::CopyCpuToGpu(const int64_t &device_id, const Config &config) {
     if (auto res = FaissGpuResourceMgr::GetInstance().GetRes(device_id)) {
         ResScope rs(res, device_id, false);
         faiss::gpu::GpuClonerOptions option;
@@ -95,11 +98,13 @@ VectorIndexPtr IVFSQHybrid::CopyCpuToGpu(const int64_t &device_id, const Config
     }
 }
 
-void IVFSQHybrid::LoadImpl(const BinarySet &index_binary) {
+void
+IVFSQHybrid::LoadImpl(const BinarySet &index_binary) {
     FaissBaseIndex::LoadImpl(index_binary); // load on cpu
 }
 
-void IVFSQHybrid::search_impl(int64_t n,
+void
+IVFSQHybrid::search_impl(int64_t n,
                               const float *data,
                               int64_t k,
                               float *distances,
@@ -112,7 +117,8 @@ void IVFSQHybrid::search_impl(int64_t n,
     }
 }
 
-QuantizerPtr IVFSQHybrid::LoadQuantizer(const Config &conf) {
+QuantizerPtr
+IVFSQHybrid::LoadQuantizer(const Config &conf) {
     auto quantizer_conf = std::dynamic_pointer_cast<QuantizerCfg>(conf);
     if (quantizer_conf != nullptr) {
         quantizer_conf->CheckValid(); // throw exception
@@ -140,7 +146,8 @@ QuantizerPtr IVFSQHybrid::LoadQuantizer(const Config &conf) {
     }
 }
 
-void IVFSQHybrid::SetQuantizer(QuantizerPtr q) {
+void
+IVFSQHybrid::SetQuantizer(const QuantizerPtr& q) {
     auto ivf_quantizer = std::dynamic_pointer_cast<FaissIVFQuantizer>(q);
     if (ivf_quantizer == nullptr) {
         KNOWHERE_THROW_MSG("Quantizer type error");
@@ -158,5 +165,15 @@ void IVFSQHybrid::SetQuantizer(QuantizerPtr q) {
     }
 }
 
+void
+IVFSQHybrid::UnsetQuantizer() {
+    auto *ivf_index = dynamic_cast<faiss::IndexIVF *>(index_.get());
+    if(ivf_index == nullptr) {
+        KNOWHERE_THROW_MSG("Index type error");
+    }
+
+    ivf_index->quantizer = nullptr;
+}
+
 }
 }
diff --git a/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.h b/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.h
index 020fe110b40c23dd815b098e54c05aba3b3ad870..f2f7c2003921cb9a19c73b521b306591bb08dbb6 100644
--- a/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.h
+++ b/cpp/src/core/knowhere/knowhere/index/vector_index/IndexIVFSQHybrid.h
@@ -49,7 +49,10 @@ class IVFSQHybrid : public GPUIVFSQ {
     LoadQuantizer(const Config &conf);
 
     void
-    SetQuantizer(QuantizerPtr q);
+    SetQuantizer(const QuantizerPtr& q);
+
+    void
+    UnsetQuantizer();
 
     IndexModelPtr
     Train(const DatasetPtr &dataset, const Config &config) override;
diff --git a/cpp/src/wrapper/VecImpl.cpp b/cpp/src/wrapper/VecImpl.cpp
index 0bbe97cbbed1b265911146b241938ba36fc26ddf..4530757f6810facda4e2e0343b97f92c71aadc02 100644
--- a/cpp/src/wrapper/VecImpl.cpp
+++ b/cpp/src/wrapper/VecImpl.cpp
@@ -277,7 +277,8 @@ IVFMixIndex::Load(const zilliz::knowhere::BinarySet &index_binary) {
     return Status::OK();
 }
 
-knowhere::QuantizerPtr IVFHybridIndex::LoadQuantizer(const Config& conf) {
+knowhere::QuantizerPtr
+IVFHybridIndex::LoadQuantizer(const Config& conf) {
     // TODO(linxj): Hardcode here
     if (auto new_idx = std::dynamic_pointer_cast<knowhere::IVFSQHybrid>(index_)){
         return new_idx->LoadQuantizer(conf);
@@ -286,7 +287,8 @@ knowhere::QuantizerPtr IVFHybridIndex::LoadQuantizer(const Config& conf) {
     }
 }
 
-Status IVFHybridIndex::SetQuantizer(knowhere::QuantizerPtr q) {
+Status
+IVFHybridIndex::SetQuantizer(const knowhere::QuantizerPtr& q) {
     try {
         // TODO(linxj): Hardcode here
         if (auto new_idx = std::dynamic_pointer_cast<knowhere::IVFSQHybrid>(index_)) {
@@ -304,6 +306,25 @@ Status IVFHybridIndex::SetQuantizer(knowhere::QuantizerPtr q) {
     }
 }
 
+Status
+IVFHybridIndex::UnsetQuantizer() {
+    try {
+        // TODO(linxj): Hardcode here
+        if (auto new_idx = std::dynamic_pointer_cast<knowhere::IVFSQHybrid>(index_)) {
+            new_idx->UnsetQuantizer();
+        } else {
+            WRAPPER_LOG_ERROR << "Hybrid mode not support for index type: " << int(type);
+            return Status(KNOWHERE_ERROR, "not support");
+        }
+    } catch (knowhere::KnowhereException &e) {
+        WRAPPER_LOG_ERROR << e.what();
+        return Status(KNOWHERE_UNEXPECTED_ERROR, e.what());
+    } catch (std::exception &e) {
+        WRAPPER_LOG_ERROR << e.what();
+        return Status(KNOWHERE_ERROR, e.what());
+    }
+}
+
 } // namespace engine
 } // namespace milvus
 } // namespace zilliz
diff --git a/cpp/src/wrapper/VecImpl.h b/cpp/src/wrapper/VecImpl.h
index 7a131f7e07fe28c03600dd104a400ed1ab25e7d1..ba0934cf923fdfc957cc383a52a4da4305c6fb9a 100644
--- a/cpp/src/wrapper/VecImpl.h
+++ b/cpp/src/wrapper/VecImpl.h
@@ -103,9 +103,14 @@ class IVFMixIndex : public VecIndexImpl {
 
 class IVFHybridIndex : public IVFMixIndex {
  public:
-    knowhere::QuantizerPtr LoadQuantizer(const Config& conf) override;
+    knowhere::QuantizerPtr
+    LoadQuantizer(const Config& conf) override;
 
-    Status SetQuantizer(knowhere::QuantizerPtr q) override;
+    Status
+    SetQuantizer(const knowhere::QuantizerPtr& q) override;
+
+    Status
+    UnsetQuantizer() override;
 };
 
 class BFIndex : public VecIndexImpl {
diff --git a/cpp/src/wrapper/VecIndex.h b/cpp/src/wrapper/VecIndex.h
index 8a9c91377bf7c47bafea18992def56d2d0e849ef..24352b8d973847ba4b2ddfe3c8b936b7a78e9254 100644
--- a/cpp/src/wrapper/VecIndex.h
+++ b/cpp/src/wrapper/VecIndex.h
@@ -105,11 +105,14 @@ class VecIndex {
 
     // TODO(linxj): refactor later
     virtual knowhere::QuantizerPtr
-    LoadQuantizer(const Config& conf) {}
+    LoadQuantizer(const Config& conf) { return Status::OK(); }
 
     // TODO(linxj): refactor later
     virtual Status
-    SetQuantizer(knowhere::QuantizerPtr q) {}
+    SetQuantizer(const knowhere::QuantizerPtr& q) { return Status::OK(); }
+
+    virtual Status
+    UnsetQuantizer() { return Status::OK(); }
 };
 
 extern Status