To delete WeChat chat history on your computer, you can follow these steps:

1. Open the WeChat application on your computer.
2. Go to the chat conversation that you want to delete.
3. Right-click on the chat conversation and select the option to delete or clear the chat history.
4. Confirm the action when prompted.

If you want to delete multiple chat conversations or all chat history at once, you can usually find an option in the settings of the WeChat application on your computer.