[Background]Investigations of the spatio-temporal characteristics of precipitation in different climatic regions of the Loess Plateau are very significant,which would be conducive to the explanation of the driving factors of environmental changes in the region. [Methods]Based on the daily precipitation data of 73 meteorological stations on the Loess Plateau from 1961 to 2014,this paper analyzed the spatiotemporal precipitation variations respectively in the whole Loess Plateau and the four climatic regions using mathematical statistics methods of coefficient of variation,concentration degree,concentration period,Mann-Kendall test and Kriging interpolation. [Results] Annual precipitation of the Loess Plateau and the four climatic regions fluctuated and declined slightly during the study period. The annual precipitation of the Loess Plateau ranged from 313. 6 mm to 657. 4 mm,with a decline rate of - 0. 79 mm/a. The annual precipitations in the whole Loess Plateau and 4 climatic regions were concentrated mostly in the summer and autumn seasons. For the whole Loess Plateau,the summer and autumn precipitation were 239. 4 mm and 108. 4 mm,respectively,which constituted 79% of the annual precipitation. Concentration period of precipitation in the whole Plateau mainly ranged from 13 July to 4 September,with most periods ( 68% of a year) concentrated in the period from 29 July to 13 August. Meanwhile,the concentration degree increased gradually during the period from 1961 to 2014,and the concentration period postponed gradually. For the spatial characteristics of precipitation in the plateau level,it decreased gradually from the southeast ( 810 mm) to the northwest ( 130 mm) ,the annual precipitation of the four regions were in the order of semi-humid region > cold and arid region > semiarid region > arid region. While the coefficient of variation of precipitation changed in an opposite way and ranged from 0. 13 to 0. 36. These all indicated that precipitation was influenced strongly by the geographic position. The concentration degree of precipitation ranged from 0. 42 to 0. 68 and increased gradually from south to north on the Loess Plateau. The concentration periods of precipitation in plain and valley areas ( e. g. ,the Wei River Valley,the Fen River Valley,and the Hetao Plain) were earlier than that in highland and mountainous areas ( e. g. ,Wutai Mountain and Longzhong Plateau) ,indicating that the terrain had strong influence on the spatial distribution of the precipitation of the Loess Plateau.[Conclusions]Caused by the different intensities of monsoon and different climatic regions,the amount, fluctuation amplitude,and concentration of precipitation were significantly different in each climatic region. The study is aimed to provide certain reference for exploring the spatio-temporal characteristics of precipitation in the Loess Plateau,reasonably allocating the water resources and planning the soil and water conservation in the Loess Plateau.