The generation estimation can provide fundamental information to construct a sustainable management system of waste electrical and electronic equipment (WEEE). However, the reliable estimation result is difficult to obtain and verify. The selection of proper approach and the improvement of data quality are both key issues for improving the generation estimation of WEEE. The present work analyzed the methodologies and applications of the generation estimation of WEEE and identified the data requirements and appropriate application conditions for each method. The selection strategy was analyzed to provide authentic estimations and sustainable management of WEEE.