diff --git a/src/operators/math/gemm.cpp b/src/operators/math/gemm.cpp
index 605fa17c3c70ec3151cc1a2fb249edab336548a1..d3e6de3134ff91f47c66c927194a5ba688e931b0 100644
--- a/src/operators/math/gemm.cpp
+++ b/src/operators/math/gemm.cpp
@@ -3230,6 +3230,8 @@ void Gemm::Sgemm_omp(int m, int n, int k, float alpha, const float *A, int lda,
 
   int L1 = 64 / max_threads * 1024;
   KC = k;
+  zero = static_cast<float *>(paddle_mobile::memory::Alloc(sizeof(float) * KC));
+  memset(static_cast<void *>(zero), 0, sizeof(float) * KC);
   if (m > n) {
     // 对 A 分块
     MC = L1 / (KC * sizeof(float));
@@ -3255,7 +3257,7 @@ void Gemm::Sgemm_omp(int m, int n, int k, float alpha, const float *A, int lda,
 
     packedB = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * KC * NC));
-    (*this.*procPackB)(KC, NC, NC % NR, B, ldb, packedB);
+    (*this.*procPackB)(KC, n, n % NR, B, ldb, packedB);
     packedA = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * MC * KC * max_threads));
   } else {
@@ -3284,12 +3286,10 @@ void Gemm::Sgemm_omp(int m, int n, int k, float alpha, const float *A, int lda,
 
     packedA = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * MC * KC));
-    (*this.*procPackA)(MC, KC, MC % MR, A, lda, packedA);
+    (*this.*procPackA)(m, KC, m % MR, A, lda, packedA);
     packedB = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * KC * NC * max_threads));
   }
-  zero = static_cast<float *>(paddle_mobile::memory::Alloc(sizeof(float) * KC));
-  memset(static_cast<void *>(zero), 0, sizeof(float) * KC);
   packedC = static_cast<float *>(
       paddle_mobile::memory::Alloc(sizeof(float) * MC * NC * max_threads));
 
@@ -3352,6 +3352,8 @@ void Gemm::SgemmWithBn_omp(int m, int n, int k, float alpha, const float *A,
 
   int L1 = 64 / max_threads * 1024;
   KC = k;
+  zero = static_cast<float *>(paddle_mobile::memory::Alloc(sizeof(float) * KC));
+  memset(static_cast<void *>(zero), 0, sizeof(float) * KC);
   if (m > n) {
     // 对 A 分块
     MC = L1 / (KC * sizeof(float));
@@ -3377,7 +3379,7 @@ void Gemm::SgemmWithBn_omp(int m, int n, int k, float alpha, const float *A,
 
     packedB = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * KC * NC));
-    (*this.*procPackB)(KC, NC, NC % NR, B, ldb, packedB);
+    (*this.*procPackB)(KC, n, n % NR, B, ldb, packedB);
     packedA = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * MC * KC * max_threads));
   } else {
@@ -3405,12 +3407,10 @@ void Gemm::SgemmWithBn_omp(int m, int n, int k, float alpha, const float *A,
 
     packedA = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * MC * KC));
-    (*this.*procPackA)(MC, KC, MC % MR, A, lda, packedA);
+    (*this.*procPackA)(m, KC, m % MR, A, lda, packedA);
     packedB = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * KC * NC * max_threads));
   }
-  zero = static_cast<float *>(paddle_mobile::memory::Alloc(sizeof(float) * KC));
-  memset(static_cast<void *>(zero), 0, sizeof(float) * KC);
   packedC = static_cast<float *>(
       paddle_mobile::memory::Alloc(sizeof(float) * MC * NC * max_threads));
 
@@ -3480,6 +3480,8 @@ void Gemm::SgemmWithPRelu_omp(int m, int n, int k, const float *A, int lda,
 
   int L1 = 8 * 1024;
   KC = k;
+  zero = static_cast<float *>(paddle_mobile::memory::Alloc(sizeof(float) * KC));
+  memset(static_cast<void *>(zero), 0, sizeof(float) * KC);
   if (m > n) {
     // 对 A 分块
     MC = L1 / (KC * sizeof(float));
@@ -3505,7 +3507,7 @@ void Gemm::SgemmWithPRelu_omp(int m, int n, int k, const float *A, int lda,
 
     packedB = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * KC * NC));
-    (*this.*procPackB)(KC, NC, NC % NR, B, ldb, packedB);
+    (*this.*procPackB)(KC, n, n % NR, B, ldb, packedB);
     packedA = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * MC * KC * max_threads));
   } else {
@@ -3533,12 +3535,10 @@ void Gemm::SgemmWithPRelu_omp(int m, int n, int k, const float *A, int lda,
 
     packedA = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * MC * KC));
-    (*this.*procPackA)(MC, KC, MC % MR, A, lda, packedA);
+    (*this.*procPackA)(m, KC, m % MR, A, lda, packedA);
     packedB = static_cast<float *>(
         paddle_mobile::memory::Alloc(sizeof(float) * KC * NC * max_threads));
   }
-  zero = static_cast<float *>(paddle_mobile::memory::Alloc(sizeof(float) * KC));
-  memset(static_cast<void *>(zero), 0, sizeof(float) * KC);
   packedC = static_cast<float *>(
       paddle_mobile::memory::Alloc(sizeof(float) * MC * NC * max_threads));