Even during the conflict, agricultural extension by the Palestinian Authority has played an important role in agricultural development in the West Bank of the Occupied Palestinian Territories (OPT). The Ministry of Agriculture of the Palestinian Authority provided the necessary agricultural extension services for Palestinian farmers affected by the Israeli settlements and Segregation Wall. Despite such importance of agricultural extension, few quantitative studies have examined its effect on Palestinian farmers. Therefore, the objective of this study was to quantify the effect of agricultural extension on technology adoption by Palestinian farmers for appropriate evaluation of the agricultural policies by the Palestinian Authority. The microdata of 79,446 agricultural holdings from the Agricultural Census 2010, which was the only microdata officially published and available at the time of this study, was used. Then, the Propensity Score Matching (PSM) method was employed to mitigate the endogenous bias caused by self-selection by farmers in receiving the agricultural extension. The results showed that agricultural extension has positively and significantly affected the adoption of five technologies, namely improved crop varieties, chemical fertilizers, organic fertilizers, pesticides, and biological control. The estimated increase in the adoption rate of those technologies as the average treatment effects on the treated (ATT) by the nearest-neighbor matching method were by 7.1, 7.7, 5.4, 6.8, and 3.8 percentage points respectively. This study proved that agricultural extension promoted the adoption of those technologies even in the conflict. Therefore, agricultural extension by the Palestinian Authority plays an important role in farming by Palestinian farmers. In order to maintain and improve farmers’ livelihoods sustainably, it is necessary to continue the agricultural extension by the Palestinian Authority in the future, considering the behavior of farmers.