A yield gap analysis for rapeseed (Brassica napus L.) is critical to meeting the oil demand by identifying yield potential and yield constraints. In this study, potential yield (Y_p), attainable yield (Y_att), and actual yield (Y_act) for winter rapeseed were determined in five different zones of China.  A boundary line approach was adopted to calculate Yp, based on a large-scale field experimental database.  A meta-analysis was conducted on the data obtained from 118 published studies to evaluate the effects of agronomic factors on rapeseed yield.  The main results indicated that farmers only achieved 37–56% of the yield potential across the zones.  The low altitude areas (L-URY) and lower reaches (LRY) of the Yangtze River Basin (YRB), China had high yield levels.  The total yield gap was 1 893 kg ha^–1, due to the agronomic management factors, environmental factors, and socioeconomic factors.  The meta-analysis showed that weed control and drainage were the best management practices to improve yields (45.6 and 35.3%, respectively), and other practices improved yields by 17.1–21.6%.  Consequently, to narrow the yield gap over the short term, the study could focus on techniques that are easily implemented to farmers.