The invention relates to a guest greeting robot small arm control device. The guest greeting robot small arm control device comprises a body and a head, wherein the head is mounted on the body. The left side and the right side of the body are each fixedly provided with a large arm. A small arm is hinged to the front end of each large arm. The middle and the upper end of each small arm are providedwith a protruding block and a palm correspondingly. A motor is mounted in the middle of the body and connected with a straight gear. The straight gear is engaged with an outer gear ring. A round roller is fixedly mounted on the inner side wall of the outer gear ring. The left end and the right end of the body are each provided with an inclined face. A transmission rod bracket is in abutting fit with the eccentric position of each inclined face. The guest greeting robot small arm control device is high in intelligentization level; the two transmission rod brackets are driven by rotation of theround roller to maintain opposite reciprocating type sliding, and furthermore, the two palms can be driven to maintain waving continuously in opposite gestures; the effect that hand waving for greeting is conducted in a highly-human-simulating manner is achieved; and the good greeting effect is achieved.