Abstract: The pathway to the maxillary sinus area is anatomically curved and narrow. Thus, using the conventional approach based on the straight endoscope and surgical tools, there are some limitations in inspection and treatment of the target legion of the maxillary sinus. To cope with such problems, a dual master-slave system is investigated in this work for general maxillary sinus surgery. Initially, the need for dual arm operation is explained. A compact design of two 4-DOF end-effector mechanisms for acquiring the endoscopic image and performing biopsy is introduced. Next, a dual master device to control the motions of the two end-effector mechanisms is employed and a motion scheduling algorithm for a proper master-slave control is also developed. Finally, the feasibility of the dual master-slave system is verified through experimental work.