In this paper, a control method for pushing operation by a mobile manipulator with dual arms is proposed. The mobile manipulator is able to perform various tasks because of mobility of a platform and manipulability of dual arms. This research focuses on pushing operation in human environments. Important factors in pushing operation are safety and configuration of operational object. In conventional research, compliance control was applied for safety because compliance control enables robots to contact compliantly. However, application of compliance control to robot with dual arms has room for improvements in stability of configuration when bias of road friction distribution exists. This research realizes stable configuration for operational object by varying compliance gains of each arm according to estimated road friction force by Extended Kalman filter. The validity of proposed method is verified by the simulation results.