This paper describes in brief the achievements of barometric altimetry in high-precision aeromagnetic survey.The main technical indices and standardization of 1241Mtype miniature barometric altitude sensor are given first. Tests demonstrate the necessity of barometric altitude daily variation survey and the optimum control limits for setting up the station.The factors affecting the precision of barometric altimetry are investigated in several aspects. The accuracy of barometric altimetry of 124Msystem is te sted by utilizing known elevation points of China. The comparison of 55 points shows that the accuracy is higher than + 5m. Under the ideal condition, the flight at different heights over the runway of the airport suggests that this method is quite consistent with such radio altimetric techniques as 263,265 and ALT-55.Acomplete set of barometric altimetric techniques and data-processing me thods suitable for high -precision aeromagnetic survey in China has been deve loped. The practical work performed in1985 and 1987 all reaches the high pre cision of above -10m, demonstrating that this set of methods is feasible and technically advanced, has high-precision and can yield reliable results.