Analyzing the changes in potential evapotranspiration (ET₀) and the attribution is an important way to understand hydrologic process and its response to climate change. In this study, after applying the FAO Penman-Monteith equation to estimate the ET₀ in the Weihe River Basin for the period of 1960-2016, the differential method was employed to quantify the contribution of the four meteorological factors, i.e. solar radiation (R_s), wind speed (u₂), relative humidity (RH), and average temperature (T), to the ET₀ changes. The main results are shown below. During the 57 years, annual ET₀ showed a slightly increasing trend of 0.239 mm/a, and multi-year average annual ET₀ increased from the west to the east and from the south to the north of the basin spatially. We found that annual ET₀ was most sensitive to RH, followed by R_s and T, and least sensitive to u₂. Moreover, the sensitivity coefficients of T and u₂ decreased with increasing elevation. From the perspective of contribution, the changes in T contributed most to the changes of annual ET₀, followed by u₂ and RH, and the changes in R_s showed the smallest contribution to annual ET₀ changes. Generally speaking, the negative effects caused by the decrease in R_s and u₂ to annual ET₀ changes were offset by the positive effects caused by the increase in T and decrease in RH, which finally resulted in the increasing trend in annual ET₀ during 1960-2016 in the whole basin. Since the correlation among the meteorological factors may influence their individual contribution to ET₀ changes, we can fully discuss the attribution of ET₀ changes by considering the interactions between these factors in practice. This study is significant for understanding the influence mechanism of climate change to hydrologic cycle as well as improving our capacity to cope with climate change regionally.