Abstract: The research aims to obtain baseline information of the impacts of room temperature on lactating sow behaviour and pre-weaning piglet creep box usage. Twelve Yorkshire pregnant sows were randomly assigned to hot (30.4℃) and warm room temperature groups (15.3℃), i.e. 6 sows per treatment. Results demonstrated the pre-weaning piglet creep box usage for warm litters (62.4%) was higher than that of hot litters (1%). Sows from warm group had higher time partitioning (%) in standing and kneeling than that of sows from hot group. The warm sows showed longer transition (falling) time from standing to lying, as compared to the hot sows, respectively (4.0 s vs 3.4 s). The frequency of posture transition from sitting to belly lying or versa of warm sows was lower than that of hot sows (P＜0.01). No piglet was crushed in warm group, but there was a higher pre-weaning piglet crushing mortality (15.2%) in hot group. Piglet from warm group showed better growth performance and higher average daily gain than those from hot groups. The present study suggest a suitable temperature gradient between creep box and farrowing room was conducive to increasing the box usage and hence decreasing crushing mortality for pre-weaning piglets.