The application discloses a base assembly and a child safety seat. The base assembly includes: a base including a base bracket; a support leg; a slider including a slider bracket, the slider bracket being disposed slidably on the base bracket, and the support leg being pivotably connected to the slider and telescoped with the slider; and a locking member for locking the slider bracket to the base bracket. The base assembly and the child safety seat provided by the application simplify the operation of the user, so that the operation is simple and convenient, and the user experience is improved

The present disclosure discloses a multifunctional side impact block control system and a child safety seat including the same. The multifunctional side impact block control system includes a seat body, a side impact block movably mounted on a left side surface and/or a right side surface of the seat body, a main controller, and a functional module integrated in the side impact block. The side impact block and the functional module are in communication connection with the main controller. The functional module includes one or more of an interaction unit, an entertainment unit, an environment adjustment unit, a safety unit, and a welcoming unit. The side impact block movably mounted on the side surface of the seat body can be easily operated by a user, making the interaction more intuitive and providing a control region that better meets the requirements in practical applications, thereby providing great convenience.