An actuating motor set includes a mounting base; a motor; a transmission set including a worm gear formed with a tooth, wherein two opposite ends of the worm gear respectively defining are a pushing end and a restoring end; and a spring including an engagement part and an abutment part. The engagement part is engaged with the tooth, and an inner diameter of the abutment part is larger than an outer diameter of the tooth. The spring is pushed spirally by the tooth upon rotation of worm gear, and thus moving back and forth on an axial direction of the worm gear. The spring idles when it is moved to the pushing end due to lack of engagement therewith, and the spring also idles when it is moved the restoring end due to lack of engagement therewith.