diff --git a/lib/c-api/src/wasm_c_api/externals/function.rs b/lib/c-api/src/wasm_c_api/externals/function.rs
index 7db2b533d4d..da8d851fe38 100644
--- a/lib/c-api/src/wasm_c_api/externals/function.rs
+++ b/lib/c-api/src/wasm_c_api/externals/function.rs
@@ -6,7 +6,7 @@ use super::CApiExternTag;
 use std::convert::TryInto;
 use std::ffi::c_void;
 use std::mem::MaybeUninit;
-use std::sync::Arc;
+use std::sync::{Arc, Mutex};
 use wasmer_api::{Function, RuntimeError, Val};
 
 #[derive(Debug, Clone)]
@@ -110,7 +110,7 @@ pub unsafe extern "C" fn wasm_func_new_with_env(
     #[repr(C)]
     struct WrapperEnv {
         env: *mut c_void,
-        env_finalizer: Arc<Option<wasm_env_finalizer_t>>,
+        env_finalizer: Arc<Mutex<Option<wasm_env_finalizer_t>>>,
     }
 
     impl wasmer_api::WasmerEnv for WrapperEnv {}
@@ -122,8 +122,12 @@ pub unsafe extern "C" fn wasm_func_new_with_env(
 
     impl Drop for WrapperEnv {
         fn drop(&mut self) {
-            if let Some(env_finalizer) = *self.env_finalizer {
-                unsafe { (env_finalizer)(self.env as _) }
+            if let Ok(mut guard) = self.env_finalizer.lock() {
+                if Arc::strong_count(&self.env_finalizer) == 1 {
+                    if let Some(env_finalizer) = guard.take() {
+                        unsafe { (env_finalizer)(self.env as _) };
+                    }
+                }
             }
         }
     }
@@ -166,7 +170,7 @@ pub unsafe extern "C" fn wasm_func_new_with_env(
         func_sig,
         WrapperEnv {
             env,
-            env_finalizer: Arc::new(env_finalizer),
+            env_finalizer: Arc::new(Mutex::new(env_finalizer)),
         },
         trampoline,
     );