A cockroach trap includes a case including an opening and first and second compartments a guide assembly disposed above the first compartment and including a channel communicating with the opening, and a bossed hole communicating with the channel an open reservoir releasably disposed in the first compartment a bait passageway in an upper portion of the reservoir and communicating with both the channel and the reservoir an entrance sensor disposed proximate the channel a pivotal trigger disposed above the second compartment and including a projection and an air canister releasably disposed in the second compartment and including a plunger engaged with the projection, a nozzle, and a line having two ends connected to the nozzle and the bossed hole respectively. After the entrance sensor is activated, the projection presses the plunger to open the nozzle, thereby communicating the nozzle with the air canister.
