Since 1984, Korean WCC area has been spread rapidly. Annual groundwater use in WCC area has been estimated to be 5.4~5.7 m3/y, which is equivalent to 32~35% of agricultural groundwater use in Korea. The WCC usually begins at November and ends at March every year. Therefore, every year starting from November, groundwater level in WCC area gradually declines and reaches to its lowest level at March. Thus one of problems related to WCC in Korea includes severe shortage of groundwater resources during the peak season. Because nearby stream water is definitely introduced into the aquifer system due to much lower level of groundwater compared to stream water during WCC peak time, it is likely that the problem can be resolved efficiently if the connection characteristics between groundwater aquifer and stream water are well understood. In order to understand the connection between stream and ground water, and the influence of stream water on the nearby aquifer, this study examined temperature, and oxygen/hydrogen stable isotopic compositions for both stream and ground water extracted from wells. This study was performed at Wangjeon-ri of Nonsan City, which is one of well-known strawberry WCC areas in Korea. The study area covers about 1.2 km2 in which about 74% of 291 vinyl house used to be applied for WCC. Water sampling was done during February 2010 through June 2011. Groundwater temperatures for 51 wells were measured to be ranged from 9.8 to 16.3 ℃, and mostly 14.6 ℃. Inflection point for water temperatures was identified at the zone of 140 m to 160 m distance from the stream, which might be inferred to be range of intensive intrusion of stream water into aquifer. Overall temperature distribution pattern indicates that Noseongcheon stream water widely intruded into the surrounding aquifer and affected groundwater temperature obviously in the southern right part of WCC area. However, in the southern left part, the influence of stream water into aquifer seems to occur in very narrow restricted range near the stream. This phenomenon can be similarly found by the oxygen and hydrogen isotopic data. There are two possible end members affecting water quality in aquifers beneath WCC area; groundwater in the northern rolling hill part (δ18O = - 7.71 ~ -7.59 ‰ (- 7.62 ‰ in average), δD = - 54.1~ - 53.7 ‰ (- 54.9 ‰ in average)) and Noseongcheon stream water in the southern area (δ18O = - 6.86 ~ - 6.66 ‰ (-6.74 ‰ in average), δD = - 49.7 ~ - 47.8 ‰ (- 48.1 ‰ in average)). The average values can be used for estimation of mixing ratios in each point of WCC area between stream water and groundwater recharging from northern rolling hills.