Due to the increase in the number of people in our families, child seats are restricted by the family space, and the children's living space will become smaller, and the cost of family living will also increase. Although there are a large number of domestic child seat brands, they are still dominated by child seats with single function and fixed form, but the physical and psychological growth laws of children are changeable and infinitive, and the seat products used at different ages are also very different, so the existing child seats are difficult to meet the growth needs of children, which also leads to many parents having to buy or refuse to buy children's products again [1]. Therefore, the design of growing child seats has the characteristics of versatility, sustainability, entertainment, economy and other characteristics, which can effectively meet the seat needs of children at different ages.This design is a growing child modular seat, which can be designed to assemble five products with different functions, namely a growth chair, stroller, crib, walker and slide. All combinations share a common framework, which can be freely matched and playable, and can be selected according to actual needs. Built-in storage box design to meet the needs of the trolley when traveling to store items; Shock-absorbing design, more friendly to babies when traveling on the road section; Seat adjustment design, the seat height can be selected according to actual needs; The awning is recognized, which solves the problem of comfortable travel in all kinds of weather; The push handle adjustment design allows users to choose the appropriate angle and height according to their needs; The whole car can be folded to facilitate travel and storage, which is suitable for families with children aged 0 to 12.