Abstract: Ecosystem service value (ESV) calculation is a focus of ecological economics and is key in ecological compensation. Contingent valuation method (CVM) was used to measure ecosystem service value in Weigan River Basin, one of nine branches of Tarim River Basin and the largest inland river in arid China, in terms of the willingness to pay (WTP). Pearson correlation coefficients and multiple linear regressions were used to analyze relations between socio-economic variables and WTP. The results indicated that: 1) mean value of WTP for ecosystem services in Weigan River Basin was 96.22 Yuan per household per annum. While this was lower than that in river basins in East China and other countries, it was close to that in river basins in Northwest China. Residents' chosen WTP was 110.87~157.58 Yuan and 55.8~102.37 Yuan per household per annum in the up and down stream regions of the basin, respectively. Total annual value of ecosystem services in the basin was 24.43 million Yuan. 2) Residents' chosen WTP was positively correlated with income level, education level, household registration and cognitive level of importance of ecological environment. It was, however, negatively correlated with payment. Gender and age did not obvious influence residents' chosen WTP. Residents' chosen WTP in towns was higher than that in rural area, but not in upstream. Relationship between WTP and the influencing factors was different for upstream and downstream regions. 3) The most critical WTP factor was income level (with a standardized coefficient of 0.604), followed by household cognitive level, payment and the education level. Effective options were advanced to improve watershed residents' WTP, including addressing poverty of local residents, strengthening publicity of the importance of ecological environment, enhancing residents' education level and selecting appropriate payments that took into account residents with different household registrations and regions. 4) CVM results were similar for similar regions, and consistent with the results obtained by remote sensing methods. Ecosystem service values calculated by different methods were different in the same basin. The study presented problems and solutions of multiple co-linearity analysis in multiple regressions. The study enriched CVM application in minority areas in arid inland river basins. The results were important justification for appropriate adjustments in payments for ecological services.