This paper analysed the large-scale circulation pattern and synoptic systems of the rare heavy rainfall occurred in the gobi desert in the middle part of the Gansu Hexi Corridor.The results showed that the large-scale rainfall occurred in the gobi desert in June 1987 was derived from the common effects of the three synoptic systems which were the short-wave trough of low pressure with surface cold front,the Qaidam depression and the low-level easterly jet along the Gansu Hexi Corridor.The results also indicated that the centre of heavy rainfall in Jinchang was derived from the mesoscale convective system formed by the release of instability energy aroused by the intruding of cold front.