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The statistical results from the rain gauge data extracted every 5 minutes are used to analyze the temporal spatial distribution variations of short period heavy precipitation in Dujiangyan. The results show: (1) the maximum of hourly rainfall occurs usually in high altitude areas. The maximum hourly rainfall has a big weight in total precipitation in the same event, which reflects that the rainfall in Dujiangyan is characterized by high intensity and concentrative precipitation time. (2) Influenced by the effect of landform and the radiative cooling of cloud tops, short period heavy precipitation in Dujiangyan primarily occurs at night, and there occur more freguently rains after midnight than before midnight. (3) Heavy precipitation occurs first along the windward slope of the mountains in summer, and afterwards，convection systems move towards southeast areas. (4) The durations of short period heavy precipitation in Dujiangyan are calculated. The precipitation duration ranges from 60 to 130 minutes generally, with the maximum up to 210 minutes.