diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Extensions/WechatTenpayClientExecuteBillExtensions.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Extensions/WechatTenpayClientExecuteBillExtensions.cs
index cef4cdc2..c7a0e12c 100644
--- a/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Extensions/WechatTenpayClientExecuteBillExtensions.cs
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Extensions/WechatTenpayClientExecuteBillExtensions.cs
@@ -93,6 +93,34 @@ namespace SKIT.FlurlHttpClient.Wechat.TenpayV3
             return await client.SendRequestWithJsonAsync<Models.GetBillFundflowBillResponse>(flurlReq, cancellationToken: cancellationToken);
         }
 
+        /// <summary>
+        /// <para>异步调用 [GET] /bill/sub-merchant-fundflowbill 接口。</para>
+        /// <para>REF: https://pay.weixin.qq.com/wiki/doc/apiv3_partner/apis/chapter4_1_12.shtml </para>
+        /// </summary>
+        /// <param name="client"></param>
+        /// <param name="request"></param>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public static async Task<Models.GetBillSubMerchantFundflowBillResponse> ExecuteGetBillSubMerchantFundflowBillAsync(this WechatTenpayClient client, Models.GetBillSubMerchantFundflowBillRequest request, CancellationToken cancellationToken = default)
+        {
+            if (client is null) throw new ArgumentNullException(nameof(client));
+            if (request is null) throw new ArgumentNullException(nameof(request));
+
+            IFlurlRequest flurlReq = client
+                .CreateRequest(request, HttpMethod.Get, "bill", "sub-merchant-fundflowbill")
+                .SetQueryParam("sub_mchid", request.SubMerchantId)
+                .SetQueryParam("bill_date", request.BillDateString)
+                .SetQueryParam("algorithm", request.Algorithm);
+
+            if (!string.IsNullOrEmpty(request.AccountType))
+                flurlReq.SetQueryParam("account_type", request.AccountType);
+
+            if (!string.IsNullOrEmpty(request.TarType))
+                flurlReq.SetQueryParam("tar_type", request.TarType);
+
+            return await client.SendRequestWithJsonAsync<Models.GetBillSubMerchantFundflowBillResponse>(flurlReq, cancellationToken: cancellationToken);
+        }
+
         /// <summary>
         /// <para>异步调用 [GET] /{download_url} 接口。</para>
         /// <para>REF: https://pay.weixin.qq.com/wiki/doc/apiv3/apis/chapter3_1_8.shtml </para>
diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Models/Bill/GetBillSubMerchantFundflowBillRequest.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Models/Bill/GetBillSubMerchantFundflowBillRequest.cs
new file mode 100644
index 00000000..cb820c6e
--- /dev/null
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Models/Bill/GetBillSubMerchantFundflowBillRequest.cs
@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+
+namespace SKIT.FlurlHttpClient.Wechat.TenpayV3.Models
+{
+    /// <summary>
+    /// <para>表示 [GET] /bill/sub-merchant-fundflowbill 接口的请求。</para>
+    /// </summary>
+    public class GetBillSubMerchantFundflowBillRequest : GetBillFundflowBillRequest
+    {
+        /// <summary>
+        /// 获取或设置子商户号。
+        /// </summary>
+        [Newtonsoft.Json.JsonIgnore]
+        [System.Text.Json.Serialization.JsonIgnore]
+        public string SubMerchantId { get; set; } = string.Empty;
+
+        /// <summary>
+        /// 获取或设置加密算法。
+        /// <para>默认值：<see cref="Constants.EncryptionAlgorithms.AEAD_AES_256_GCM"/></para>
+        /// </summary>
+        [Newtonsoft.Json.JsonIgnore]
+        [System.Text.Json.Serialization.JsonIgnore]
+        public string Algorithm { get; set; } = Constants.EncryptionAlgorithms.AEAD_AES_256_GCM;
+    }
+}
diff --git a/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Models/Bill/GetBillSubMerchantFundflowBillResponse.cs b/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Models/Bill/GetBillSubMerchantFundflowBillResponse.cs
new file mode 100644
index 00000000..e863a96c
--- /dev/null
+++ b/src/SKIT.FlurlHttpClient.Wechat.TenpayV3/Models/Bill/GetBillSubMerchantFundflowBillResponse.cs
@@ -0,0 +1,73 @@
+using System;
+using System.Collections.Generic;
+
+namespace SKIT.FlurlHttpClient.Wechat.TenpayV3.Models
+{
+    /// <summary>
+    /// <para>表示 [GET] /bill/sub-merchant-fundflowbill 接口的响应。</para>
+    /// </summary>
+    public class GetBillSubMerchantFundflowBillResponse : WechatTenpayResponse
+    {
+        public static class Types
+        {
+            public class DownloadBill
+            {
+                /// <summary>
+                /// 获取或设置账单文件序号。
+                /// </summary>
+                [Newtonsoft.Json.JsonProperty("bill_sequence")]
+                [System.Text.Json.Serialization.JsonPropertyName("bill_sequence")]
+                public int BillSequence { get; set; }
+
+                /// <summary>
+                /// 获取或设置哈希类型。
+                /// </summary>
+                [Newtonsoft.Json.JsonProperty("hash_type")]
+                [System.Text.Json.Serialization.JsonPropertyName("hash_type")]
+                public string HashType { get; set; } = default!;
+
+                /// <summary>
+                /// 获取或设置哈希值。
+                /// </summary>
+                [Newtonsoft.Json.JsonProperty("hash_value")]
+                [System.Text.Json.Serialization.JsonPropertyName("hash_value")]
+                public string HashValue { get; set; } = default!;
+
+                /// <summary>
+                /// 获取或设置账单下载地址。
+                /// </summary>
+                [Newtonsoft.Json.JsonProperty("download_url")]
+                [System.Text.Json.Serialization.JsonPropertyName("download_url")]
+                public string DownloadUrl { get; set; } = default!;
+
+                /// <summary>
+                /// 获取或设置账单加密密钥（需使用商户私钥解密）。
+                /// </summary>
+                [Newtonsoft.Json.JsonProperty("encrypt_key")]
+                [System.Text.Json.Serialization.JsonPropertyName("encrypt_key")]
+                public string EncryptKey { get; set; } = default!;
+
+                /// <summary>
+                /// 获取或设置账单加密使用的随机字符串。
+                /// </summary>
+                [Newtonsoft.Json.JsonProperty("nonce")]
+                [System.Text.Json.Serialization.JsonPropertyName("nonce")]
+                public string Nonce { get; set; } = default!;
+            }
+        }
+
+        /// <summary>
+        /// 获取或设置账单文件总数。
+        /// </summary>
+        [Newtonsoft.Json.JsonProperty("download_bill_count")]
+        [System.Text.Json.Serialization.JsonPropertyName("download_bill_count")]
+        public int DownloadBillCount { get; set; }
+
+        /// <summary>
+        /// 获取或设置账单文件列表。
+        /// </summary>
+        [Newtonsoft.Json.JsonProperty("download_bill_list")]
+        [System.Text.Json.Serialization.JsonPropertyName("download_bill_list")]
+        public Types.DownloadBill[] DownloadBillList { get; set; } = default!;
+    }
+}