Walnut blight (WB), caused by the bacterium Xanthomonas arboricola pv. juglandis,continues to be a serious disease of walnut in northern China, where weather conditions favor disease development. From 2013 to 2017, WB incidences in walnut cv. ‘Liaoning 1’ were investigated in three areas (Dalian,Suizhong and Jianchang areas) in the Liaoning province, northeastern China. WB incidence was high in Dalian (23.72%) and Suizhong (24.31%) but was low in Jianchang (12.98%). Relative humidity is a key meteorological factor that affected the differences between areas. Ten walnut cultivars were surveyed in 2013, 2015, and 2017 for their susceptibility to blight. Lateral-bearing walnut cultivars showed a higher incidence and were found more susceptible to WB compared with terminal-bearing cultivars. In order to test the most effective chemical spray methods, bactericide screening trials were conducted comprising 12 different types of bactericides and mixtures in 2015. The combination of kasugamycin+mancozeb was most effective in controlling WB incidence resulting in lowest fruit disease incidence (2.63%). Subsequently, minimal spray trials were studied to determine the most effective chemical control as well as timing and frequency of application in 2017. The study confirmed these results of studies done in California: the best timing for the first spray application was at 30%–40% pistillate flower emergence and subsequently spray times were at 6 days and 16 days interval. Results of this study provide essential information to better understand the complexity of this walnut disease toward developing effective control management strategies globally.