A plug valve, comprising: a body; a valve seat mounted on the body and having a hollow mounting column provided thereon, the mounting column having a first space and a second space that are defined in a circumferential sidewall thereof; a valve stem disposed on the valve seat and penetrating the mounting column, wherein the valve stem has one trigger groove defined in an outer peripheral surface thereof, and the trigger groove comprises an upper trigger surface and a lower trigger surface; a first switch mounted on the valve seat and comprising a first trigger terminal penetrating the first space; and the second switch mounted on the valve seat and comprising a second trigger terminal penetrating the second space, wherein the plug valve is configured in a manner that: when the valve stem is pressed, the first trigger terminal is triggered by the upper trigger surface to enable the first switch to be in a first state, and the second trigger terminal is triggered by the lower trigger surface to enable the second switch to be in a second state; and when the valve stem is released from pressing, the first trigger terminal is triggered by the upper trigger surface to enable the first switch to be in a third state, and the lower trigger surface enables the second switch to be kept in the second state or the second trigger terminal is triggered by the lower trigger surface to enable the second switch to be in a fourth state. a body; a valve seat mounted on the body and having a hollow mounting column provided thereon, the mounting column having a first space and a second space that are defined in a circumferential sidewall thereof; a valve stem disposed on the valve seat and penetrating the mounting column, wherein the valve stem has one trigger groove defined in an outer peripheral surface thereof, and the trigger groove comprises an upper trigger surface and a lower trigger surface; a first switch mounted on the valve seat and comprising a first trigger terminal penetrating the first space; and the second switch mounted on the valve seat and comprising a second trigger terminal penetrating the second space, wherein the plug valve is configured in a manner that: when the valve stem is pressed, the first trigger terminal is triggered by the upper trigger surface to enable the first switch to be in a first state, and the second trigger terminal is triggered by the lower trigger surface to enable the second switch to be in a second state; and when the valve stem is released from pressing, the first trigger terminal is triggered by the upper trigger surface to enable the first switch to be in a third state, and the lower trigger surface enables the second switch to be kept in the second state or the second trigger terminal is triggered by the lower trigger surface to enable the second switch to be in a fourth state. when the valve stem is pressed, the first trigger terminal is triggered by the upper trigger surface to enable the first switch to be in a first state, and the second trigger terminal is triggered by the lower trigger surface to enable the second switch to be in a second state; and when the valve stem is released from pressing, the first trigger terminal is triggered by the upper trigger surface to enable the first switch to be in a third state, and the lower trigger surface enables the second switch to be kept in the second state or the second trigger terminal is triggered by the lower trigger surface to enable the second switch to be in a fourth state.