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Field studies were conducted for two consecutive years in Korla, Xinjiang, China, to investigate the response of pear trees to different surface wetted percentages under drip irrigation on an oasis around Taklimakan desert. The 24-year-old pear trees were weekly irrigated at a level to replace 80% of the US Class A Pan evaporation, with three different surface wetted percentages: 16, 32 and 43%. A control (CK) was flood irrigated with a monthly applied amount of 300 mm. All drip irrigated treatments applied about 50% water less than control. A larger (43%) surface wetting had a significantly low yield (two year average of 17% reduction) than the flood irrigated treatment, but there were no significant yield differences among the other treatments. Maximum irrigation water use efficiency was observed in 32% surface wetting (on an average 3.02 kg/m(3)). However, there was a significant reduction in the mass of new shoots with drip irrigation. Under the extremely arid climatic conditions of this study, during the initial period, 32% surface wetted percentage proved optimal for mature pear trees that had been transferred from flood irrigation into drip irrigation. (C) 2012 Friends Science Publishers