The working principle of αβ filter is studied， and the functional expressions of the filter in the discrete and continuous domains are derived. Based on the transfer function， stability analysis of the filter is carried out， and combined with the engineering design， the range of α and β parameter values that make the filter system stability are achieved. The commonly used parameter design methods are analyzed， the current problems of the filter are pointed out， and an improved adaptive αβ filter method is proposed. Finally， the influences of parameters α and β are analyzed through simulation， and the filtering performance of the improved adaptive filtering method and the traditional filtering method are compared. The simulation results showed that the selection of parameters α and β have a significant impact on the filtering effect. What’s more， the improved adaptive filtering approach has better filtering performance than traditional method， with smoother filtered data and better filtering effect on abnormal noise.