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The semi-arid area in northern China is an agro-pastoral transition zone. The environment there is sensitive to climate variation, particularly to precipitation change. Daily precipitation records of 30-gauge stations from May to September during 1956-2000 are analysed in this study. The precipitation amounts show only slightly decreasing trends; however, some aspects of the rainfall characteristics display significant changes. Compared to the 1950s, rainy days have been reduced by about 8 days in the 1990s. Significant change is observed in the number of days when there is light rain (<10 mm day(-1)). The days with light rain also show a significant tendency toward a stronger intensity, whereas those days with moderate and above moderate rains do not. At the same time, the long duration precipitation (greater than or equal to 3days) event is found to decrease remarkably with a linear trend of -5.6% per 10 years. In contrast, the frequency of long dry spells (greater than or equal to 10 consecutive days without rainfall) is becoming more frequent at a rate of 7.2% per 10 years. Taking 30 stations as a whole the maximum daily rainfall displays no evident trend. But the median of the maximums shows a step-like drop beginning in 1979 and the low values are notable until the early 1990s. This is coincident with the large-scale climate regime shift over East Asia, probably suggesting a response of regional daily precipitation extremes due to the change of the East Asian summer monsoon system. (C) 2004 Elsevier Ltd. All rights reserved.