Abstract: A trap for mice or the like animal comprises a spring-loaded displacement member (17) supported by a frame (10) with an opening for receiving the head of the animal. The displacement member (17) is connected to the frame (10) by means of a securing line (27) extending within reach of the animal in the frame (10) inside the opening (22). The frame (10) is formed in one piece and comprises a front wall (12), in which the opening is placed and on the outside of which the displacement member (17) is arranged so as to be displaceable transverse to the opening (22). The displacement member (17) is spring-loaded by means of rubber bands (25 and 26) fastened to the frame (10) and protected on the front side of the front wall (12) by covering parts (15 and 16) formed integral with the frame. The frame (10) with the displacement member (17) is loosely placeable in a surrounding box with a closed rear wall, the opening (22) of the frame (10) facing an opening in the box.