The public square is one of the most crucial elements in urban design. And seasonal measures play a very important role in the design of public squares in cities. This study summarises several aspects of seasonal design measures, including the specific timeliness of social events, the seasonal growth of the planting landscape in public squares, and sustainable design that is compatible with the seasonal climate. It also analyses the role of seasonal measures in the design of public squares by analysing seasonal design strategies in the renovation of Shanghai People's Square. It reminds urban designers of the importance of considering seasonal measures in their work.