diff --git a/esphome/components/bluetooth_proxy/bluetooth_connection.cpp b/esphome/components/bluetooth_proxy/bluetooth_connection.cpp
index 540492f8c5..94d18ac543 100644
--- a/esphome/components/bluetooth_proxy/bluetooth_connection.cpp
+++ b/esphome/components/bluetooth_proxy/bluetooth_connection.cpp
@@ -514,7 +514,8 @@ esp_err_t BluetoothConnection::read_characteristic(uint16_t handle) {
   return this->check_and_log_error_("esp_ble_gattc_read_char", err);
 }
 
-esp_err_t BluetoothConnection::write_characteristic(uint16_t handle, const std::string &data, bool response) {
+esp_err_t BluetoothConnection::write_characteristic(uint16_t handle, const uint8_t *data, size_t length,
+                                                    bool response) {
   if (!this->connected()) {
     this->log_gatt_not_connected_("write", "characteristic");
     return ESP_GATT_NOT_CONNECTED;
@@ -523,7 +524,7 @@ esp_err_t BluetoothConnection::write_characteristic(uint16_t handle, const std::
            handle);
 
   esp_err_t err =
-      esp_ble_gattc_write_char(this->gattc_if_, this->conn_id_, handle, data.size(), (uint8_t *) data.data(),
+      esp_ble_gattc_write_char(this->gattc_if_, this->conn_id_, handle, length, const_cast<uint8_t *>(data),
                                response ? ESP_GATT_WRITE_TYPE_RSP : ESP_GATT_WRITE_TYPE_NO_RSP, ESP_GATT_AUTH_REQ_NONE);
   return this->check_and_log_error_("esp_ble_gattc_write_char", err);
 }
@@ -540,7 +541,7 @@ esp_err_t BluetoothConnection::read_descriptor(uint16_t handle) {
   return this->check_and_log_error_("esp_ble_gattc_read_char_descr", err);
 }
 
-esp_err_t BluetoothConnection::write_descriptor(uint16_t handle, const std::string &data, bool response) {
+esp_err_t BluetoothConnection::write_descriptor(uint16_t handle, const uint8_t *data, size_t length, bool response) {
   if (!this->connected()) {
     this->log_gatt_not_connected_("write", "descriptor");
     return ESP_GATT_NOT_CONNECTED;
@@ -549,7 +550,7 @@ esp_err_t BluetoothConnection::write_descriptor(uint16_t handle, const std::stri
            handle);
 
   esp_err_t err = esp_ble_gattc_write_char_descr(
-      this->gattc_if_, this->conn_id_, handle, data.size(), (uint8_t *) data.data(),
+      this->gattc_if_, this->conn_id_, handle, length, const_cast<uint8_t *>(data),
       response ? ESP_GATT_WRITE_TYPE_RSP : ESP_GATT_WRITE_TYPE_NO_RSP, ESP_GATT_AUTH_REQ_NONE);
   return this->check_and_log_error_("esp_ble_gattc_write_char_descr", err);
 }
diff --git a/esphome/components/bluetooth_proxy/bluetooth_connection.h b/esphome/components/bluetooth_proxy/bluetooth_connection.h
index e5d5ff2dd6..60bbc93e8b 100644
--- a/esphome/components/bluetooth_proxy/bluetooth_connection.h
+++ b/esphome/components/bluetooth_proxy/bluetooth_connection.h
@@ -18,9 +18,9 @@ class BluetoothConnection final : public esp32_ble_client::BLEClientBase {
   esp32_ble_tracker::AdvertisementParserType get_advertisement_parser_type() override;
 
   esp_err_t read_characteristic(uint16_t handle);
-  esp_err_t write_characteristic(uint16_t handle, const std::string &data, bool response);
+  esp_err_t write_characteristic(uint16_t handle, const uint8_t *data, size_t length, bool response);
   esp_err_t read_descriptor(uint16_t handle);
-  esp_err_t write_descriptor(uint16_t handle, const std::string &data, bool response);
+  esp_err_t write_descriptor(uint16_t handle, const uint8_t *data, size_t length, bool response);
 
   esp_err_t notify_characteristic(uint16_t handle, bool enable);
 
diff --git a/esphome/components/bluetooth_proxy/bluetooth_proxy.cpp b/esphome/components/bluetooth_proxy/bluetooth_proxy.cpp
index 532aff550e..cd7261d5e5 100644
--- a/esphome/components/bluetooth_proxy/bluetooth_proxy.cpp
+++ b/esphome/components/bluetooth_proxy/bluetooth_proxy.cpp
@@ -305,7 +305,7 @@ void BluetoothProxy::bluetooth_gatt_write(const api::BluetoothGATTWriteRequest &
     return;
   }
 
-  auto err = connection->write_characteristic(msg.handle, msg.data, msg.response);
+  auto err = connection->write_characteristic(msg.handle, msg.data, msg.data_len, msg.response);
   if (err != ESP_OK) {
     this->send_gatt_error(msg.address, msg.handle, err);
   }
@@ -331,7 +331,7 @@ void BluetoothProxy::bluetooth_gatt_write_descriptor(const api::BluetoothGATTWri
     return;
   }
 
-  auto err = connection->write_descriptor(msg.handle, msg.data, true);
+  auto err = connection->write_descriptor(msg.handle, msg.data, msg.data_len, true);
   if (err != ESP_OK) {
     this->send_gatt_error(msg.address, msg.handle, err);
   }