diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index 4a67d66..61ecca3 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -33,6 +33,10 @@ impl serde::Serialize for Error {
 fn gen_rsa_pair(merchant_id: &str, email: &str, save_path: &str) -> Result<(), Error> {
     println!("--- Begin ---");
 
+    // 创建 merchant_id 的子目录
+    let save_dir_path = format!("{}/{}", save_path, merchant_id);
+    std::fs::create_dir_all(&save_dir_path)?;
+
     // 生成 2048 位的 RSA 私钥
     let rsa = Rsa::generate(2048)?;
     // 创建私钥
@@ -52,6 +56,10 @@ fn gen_rsa_pair(merchant_id: &str, email: &str, save_path: &str) -> Result<(), E
     let bn: BigNum = BigNum::from_slice(&bytes)?;
     let serial_number = Asn1Integer::from_bn(&bn)?;
     x509_builder.set_serial_number(&serial_number)?;
+    // 保存序列号到文件
+    let serial_number_path = format!("{}/{}_serial_number.txt", save_dir_path, merchant_id);
+    let mut serial_number_file = File::create(&serial_number_path)?;
+    serial_number_file.write_all(bn.to_hex_str()?.as_bytes())?;
 
     x509_builder.set_version(2)?;
     x509_builder.set_subject_name(&x509_name)?;
@@ -67,14 +75,14 @@ fn gen_rsa_pair(merchant_id: &str, email: &str, save_path: &str) -> Result<(), E
     // 将私钥转换为 PEM 格式
     let private_key_pem = private_key.private_key_to_pem_pkcs8()?;
     // 保存私钥到文件
-    let private_key_path = format!("{}/{}_private_key.pem", save_path, merchant_id);
+    let private_key_path = format!("{}/{}_private_key.pem", save_dir_path, merchant_id);
     let mut private_key_file = File::create(&private_key_path)?;
     private_key_file.write_all(&private_key_pem)?;
 
     // // 将证书转换为 PEM 格式
     let certificate_pem = x509.to_pem()?;
     // 保存证书到文件
-    let certificate_path = format!("{}/{}_certificate.pem", save_path, merchant_id);
+    let certificate_path = format!("{}/{}_certificate.pem", save_dir_path, merchant_id);
     let mut certificate_file = File::create(&certificate_path)?;
     certificate_file.write_all(&certificate_pem)?;