diff --git a/.gitignore b/.gitignore
index d977ab76..e56df643 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 build/
+wave/
 obj/
 .vscode/
 out/
diff --git a/Makefile b/Makefile
index 625ac260..861f3a94 100644
--- a/Makefile
+++ b/Makefile
@@ -230,7 +230,10 @@ VERI_LDFLAGS = -O1
 VERI_VFLAGS = --top $(NAME) -Wno-lint -j 8 --cc --exe +define+RANDOMIZE_GARBAGE_ASSIGN --max-num-width 1048576 --compiler clang
 VERI_VFLAGS += -Mdir $(VERI_BUILD_DIR) -CFLAGS "$(VERI_CFLAGS)" -LDFLAGS "$(VERI_LDFLAGS)"
 VERI_VFLAGS += $(VERI_THREADS)
-#VERI_VFLAGS += --trace-fst
+ifeq ($(V_WAVE),1)
+VERI_VFLAGS += --trace-fst
+VERI_CFLAGS += -DV_WAVE
+endif
 
 VERI_VSRCS = ready-to-run/difftest/$(TEST_FILE).sv
 VERI_CSRCS-2 = $(EMU_GEN_SRCS)
diff --git a/README.md b/README.md
index f1d13f18..1e772881 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,7 @@ GSIM accepts chirrtl, and compiles it to C++
     ```
     $ make init
     $ make run dutName=core
+    $ make diff dutName=core # add V_WAVE=1 to generate waveform from verilated model
     ```
 + Set core to `ysyx3`, `rocket`, `small-boom`, `large-boom`, `minimal-xiangshan` or `default-xiangshan`
 
diff --git a/emu/emu.cpp b/emu/emu.cpp
index 2da5ddbb..63277c8a 100644
--- a/emu/emu.cpp
+++ b/emu/emu.cpp
@@ -117,6 +117,11 @@ void dut_hook(DUT_NAME *dut) {
 #if defined(VERILATOR)
 #include "verilated.h"
 #include REF_HEADER
+#if defined (V_WAVE)
+#include "verilated_fst_c.h"
+VerilatedFstC *tfp;
+const std::unique_ptr<VerilatedContext> contextp{new VerilatedContext};
+#endif
 static REF_NAME* ref;
 
 void ref_init(REF_NAME *ref) {
@@ -128,6 +133,16 @@ void ref_init(REF_NAME *ref) {
   ref->difftest_uart_in_ch = -1;
   ref->difftest_uart_in_valid = 0;
 #endif
+#if defined(V_WAVE)
+  Verilated::traceEverOn(true);
+  tfp = new VerilatedFstC;
+  ref->trace(tfp, 10);
+  Verilated::mkdir("wave/");
+  tfp->open("wave/V_wave.fst");
+  if(tfp->isOpen() == false){
+    printf("Fail to open wave file!\n");
+  }
+#endif
 }
 
 void ref_hook(REF_NAME *ref) {
@@ -198,8 +213,18 @@ void dut_reset() { dut->set_reset(1); dut_cycle(10); dut->set_reset(0); }
 #ifdef VERILATOR
 void ref_cycle(int n) {
   while (n --) {
+#ifdef V_WAVE
+    contextp->timeInc(1);
+#endif
     ref->clock = 0; ref->eval();
+#ifdef V_WAVE
+    tfp->dump(contextp->time());
+    contextp->timeInc(1);
+#endif
     ref->clock = 1; ref->eval();
+#ifdef V_WAVE
+    tfp->dump(contextp->time());
+#endif
   }
 }
 void ref_reset() { ref->reset = 1; ref_cycle(10); ref->reset = 0; }
@@ -267,6 +292,10 @@ int main(int argc, char** argv) {
       printf("ALL diffs: dut -- ref\n");
       printf("Failed after %ld cycles\n", cycles);
       checkSignals(false);
+#ifdef V_WAVE
+      tfp->flush();
+      tfp->close();
+#endif
       return -1;
     }
 #endif
@@ -309,4 +338,8 @@ int main(int argc, char** argv) {
       if (cycles == CYCLE_MAX_SIM) return 0;
     }
   }
+#ifdef V_WAVE
+      tfp->flush();
+      tfp->close();
+#endif
 }