The study was conducted to assess the quality of surface water environment affected by tourism activities in An Giang province. Monitoring data was collected during the period from 2009 to 2018, at three tourist areas of Nui Sam (NT1), Lam Vien Nui Cam (NT2), Tra Su Melaleuca forest (NT3). Water parameters including temperature, pH, total suspended solids (TSS), nitrate (N-NO3-), chemical oxygen demand (COD), biological oxygen demand (BOD), oil and grease and coliform were used to assess surface water quality in the study area. Surface water quality is assessed using the national technical regulation on surface water quality (QCVN 08-MT: 2015/BTNMT, column A1). The results showed that surface water quality at the sampling locations was polluted. The parameters of TSS, COD, BOD, oil and grease and Coliform exceeded the allowable limits of QCVN 08-MT: 2015/BTNMT, column A1. Water quality at the location of Tra Su Melaleuca forest was only used for navigation; the sites at  Nui Sam and Lam Vien Nui Cam were in heavy pollution. The primary results showed that tourism activities had a significant impact on water quality. Sources of impact on water quality could be from transportation, domestic wastewater and solid waste.