Abstract: The diurnal characteristics of summer precipitation and summer short-duration heavy precipitation were analyzed using rainfalldata at regional automatic weather stations from 2006 to 2013 in Tangshan. Results show that the short-duration heavy precipitation had highernocturnal frequency than overall rainfall in general. The percentage of nocturnal precipitation frequency was 66.4%; the peak value of theaccumulated rainfall amount and rainfall frequency occurs at early morning, while the valley value appears in the afternoon. The diurnal variationin the rainfall intensity had two peak value intervals. One peak value was in the afternoon and the other peak value happened in earlymorning. Nocturnal precipitation showed an increasing tendency from 2006 to 2013. The short-duration heavy precipitation diurnal variationsshowed clear regional differences. The northeast had the maximum precipitation frequency, while the southwest had the minimum frequency,but with the strongest rainfall intensity. The northeast of Tangshan has higher precipitation frequency because it was ringed on three sides bymountains in the west, east and north, so that the airflow carried by the southeast wind was often upraised by the windward slope to induce severeconvective weather. The southwest of Tangshan had the access to the sea, therefore, plenty moisture to produce strong rainfall intensity.Diurnal changes of land-sea breeze had a great role in the formation of the precipitation peaks at 16（CST）in northeast and 4 in southwest.