[Objective]Taking Meijiang river basin as a case study,this paper investigates the variations of precipitation and runoff in order to provide supports for river regulation,flood control and environmental protection.[Methods]Runoff and precipitation data during 19602013 was collected.Mathematical methods including accumulative anomaly,variation coefficient,concentration frequency and concentration period were used to investigate the variations of runoff and precipitation at decadal,annual and seasonal time scales. The hysteresis effect of runoff to precipitation was discussed.[Results]The inter-annual changes of runoff was declined at the rate of 5.79 mm/10 a.The runoff was mainly concentrated in the summer and spring time from April to September.The fluctuation of precipitation showed a slight decreasing trend in the basin.The precipitation mainly concentrated in May to June.Correlation between annual runoff and precipitation was significant(the significant level is more than 0.001,r=0.824>0.428=R_(0.001,54)).There was a hysteresis effect of runoff to precipitation,the average hysteresis period was about 21 days,and this hysteresis period was expected to increase over time.[Conclusion]Human activity may be the main reason that alters the status of land cover or the change of climate.