Monitoring of the salinity of agricultural soil and water is necessary for sustainable food production in saltaffectedreclaimed tidelands (RTLs). Soil salinity has been extensively monitored; however, little attentionhas been given to water salinity. In this study, agricultural water salinity of five RTLs located in the southwesterncoastal area of South Korea was monitored. A total of 215 water samples were collected from estuarylakes and inland streams in Bojeon (BJ), Goheung (GH), Gunnae (GN), Samsan (SS), and Youngsangang(YSG) RTLs in 2018, 2020, and 2022. Water samples were analyzed for electrical conductivity (ECw) andsodium adsorption ratio (SAR) to estimate the suitability of water salinity for agricultural uses based on theFAO guidelines. The ECw (average: 1.6 - 3.6 dS m-1) and SAR (5 - 8) were highly variable being dependent onRTL locations, water type (lake and stream), and sampling year and month. For rice cultivation, ECw of BJ,SS, and YSG RTLs was lower than the threshold ECw (2 dS m-1) for rice growth; whereas ECw of GN (2.1 ± 1.0dS m-1) and GH (3.6 ± 1.2 dS m-1) RTLs were higher than the threshold ECw. For upland crops cultivation, bothECw and SAR of five RTLs were much higher than the FAO threshold values (ECw < 0.7 dS m-1 and SAR < 3). Therefore, our resul...