The invention provides a method and switching device for configuring stack ports. A switching device in a stacking system searches in the neighbor information table to determine whether the neighbor ID carried in a stack link negotiation packet is contained in the table after it receives the stack link negotiation packet on one of its physical ports that is enabled with the stacking function. If the neighbor ID is contained in the table, the switching device adds the physical port to the stack port corresponding to the neighbor ID in the neighbor information table; if it is not contained in the table, the switching device creates a stack port not in use, creates a binding between the neighbor ID and the stack port, and adds the physical port to the stack port. The present invention can automatically configure stack ports, greatly reducing the configuration work of administrators, and avoiding stacking device faults caused by manual configuration errors at the same time.