5 rice fields divided into one large field （T0， 2 hm²） and four small fields （T1?T4， each one was 0.33 hm²） in rice-duck co-culture were used to study the effects of high temperature in summer on the behavior， weeding control efficacy， and growth performance of Wuqin 10 meat ducks.Ducks were farmed at a density of 105?225 ducks/hm²， and the experiment was conducted from June 30th to August 31st.The occurrence and duration time of the behavior of duck including swimming， resting， and feeding in the field throughout the day， and its effects on weeding were continuously observed.The data on the outdoor temperature at 08：00 and 14：00 every day， the weight gain of ducks and feed consumption every week during the period of experiment were recorded.The results showed that the peak of duck’s activity in the field occurred during the cooler periods of 05：00?10：00 and 15：00?19：00 under the condition of high temperature in summer.Ducks actively sought shade to cool off during the period of high temperature at noon.Ducks generally moved within a certain radius near the duck house， and there was almost no activity of duck at the distal region of T0 field far away the duck house.The effect of rice-duck co-culture on weeding was positively correlated with the frequency of ducks' activities in the field， and the significantly reduced frequency of ducks' activities in waterless areas resulted in poor effect of weeding.High temperature led to heat stress in ducks and significantly reduced the growth rate of ducks.It is indicated that Wuqin 10 meat ducks are suitable for the rice-duck co-culture， and its effect of weeding is positively correlated with the activity range of ducks.The high temperature in summer significantly affects the growth performance of ducks.Sunshade in sports fields， irrigation in rice fields and circular ditches can effectively alleviate the heat stress in ducks.