diff --git a/docs/API_reference/zh/peripherals/machine.UART.md b/docs/API_reference/zh/peripherals/machine.UART.md
index 2aa92fcf328d675760ea791f1a7046986e5b02fd..7b936a34841a6e51bc8ad56d1c92d0945affec3b 100644
--- a/docs/API_reference/zh/peripherals/machine.UART.md
+++ b/docs/API_reference/zh/peripherals/machine.UART.md
@@ -12,7 +12,7 @@ class machine.UART(UART.UARTn, baudrate, databits, parity, stopbits, flowctl)
 
 **参数描述：**
 
-- `UARTn` - UART编号，int类型，UARTn说明如下：<br />`UART0` - DEBUG PORT<br />`UART1` - BT PORT<br />`UART2` - MAIN PORT<br />`UART3` - USB CDC PORT (不支持BG95M3)<br />`UART4` - STDOUT PORT (仅支持EC200U/EC600U/EG915U/EG915N)
+- `UARTn` - UART编号，int类型，UARTn说明如下：<br />`UART0` - DEBUG PORT<br />`UART1` - BT PORT<br />`UART2` - MAIN PORT<br />`UART3` - USB CDC PORT (不支持BG95M3)<br />`UART4` - STDOUT PORT (仅支持EC200U/EC600U/EG915U/EG915N/EC800M)
 
 - `baudrate` - 波特率，int类型，支持常用波特率，如`4800`、`9600`、`19200`、`38400`、`57600`、`115200`、`230400`等;