A lamp tube switching circuit includes a first connector and a second connector for connecting either an LED lamp tube or a fluorescent type lamp tube, a switch module being a mechanical switch including first, second and third switches, a starter and ballast. Each of the first and second switches has a static terminal for connecting with a power supply, and four dynamic terminals for selectively connecting with the static terminal thereof. Different circuits can be configured by adjusting the connection between the static and dynamic terminals, wherein each circuit can drive a selected type of lamp tube to generate light.