One way to solve the problem of measurement precision caused by deformity for thermal expansion,friction and load etc is to use an inertial sensor to measure a change in the length of the rod on a parallel machine.However,the characteristic of dynamic measurement in the inertial sensing system and the effects of the machine’s working environment,bias error,misalignment and wide band random noise in inertial measurement data results in the inaccuracy of system measurement.Therefore,on the basis of the measurement system a new inertial sensing system is proposed;the drifting of error is restrained with a method of inertial error correction and the system’s position and the velocity state variables are predicted by the data fusion.After measuring the whole 300mm movement in an experiment,the analyses of the experimental result showed that the application of the new inertial sensing system can improve the positional accuracy about 61% and the movement precision more than 20%.Measurement results also showed that the application of the new inertial sensing system for dynamic measurement was a feasible method to improve the machine’s dynamic positioning precision.And with the further improvement of the low-cost solid-state acceleramenter technology,the application of the machine can take a higher position and make the speed dynamic accuracy possible. One way to solve the problem of measurement precision caused by deformity for thermal expansion, friction and load etc is to use an inertial sensor to measure a change in the length of the rod on a parallel machine. However, the characteristic of dynamic measurement in the inertial sensing system and the effects of the machine’s working environment, bias error, misalignment and wide band random noise in inertial measurement data results in the inaccuracy of system measurement. Before, on the basis of the measurement system a new inertial sensing system is proposed; the drifting of error is restrained with a method of inertial error correction and the system’s position and the velocity state variables are predicted by the data fusion. After measuring the whole 300 mm movement in an experiment, the analyzes of the experimental result showed that the application of the new inertial sensing system can improve the positional accuracy about 61% and the movement precision more than 20% .Measurement re sults also showed that the application of the new inertial sensing system for dynamic measurement was a feasible method to improve the machine’s dynamic positioning precision. And with the further improvement of the low-cost solid-state acceleramenter technology, the application of the machine can take a higher position and make the speed dynamic accuracy possible.