This paper researches a combined robot posture measurement system and attitude algorithm based on Beidou/iNEMO. Here designed an embedded combination attitude calculation platform cored by ARM, to calculate posture of robot in real-time under high dynamic condition, by quatemion and kalman filter technology fusing measured data of iNEMO inertial measurement unit. Meanwhile, using the Beidou receiver outputted 1pps rising edge pulse as synchronous time of subsequent data fusion, as well as its outputted navigation data aid iNEMO inertial measurement unit, fine alignment can be realized. The feasibility and correctness of the designed test has been verified, it provides robot attitude calculation with high precision, high stability, small volume, low power consumption.