The embodiment of the invention provides an application startup item loading method, device and system and a storage medium. According to the scheme, the marks corresponding to the starting items of different types are written into all the positions of the main thread data area, the starting items in the corresponding main thread data area are started along with operation of the main thread, and therefore control over the starting time of the starting items is achieved, the starting items and the service scene are started in an associated mode, the starting time of the service scene is shortened, i.e., the user waiting time is reduced. Meanwhile, due to the fact that the main thread of the application program is written into a data area of the main thread before running, starting items executed by the application program can be conveniently customized in all service scenes, code coupling is reduced, maintenance is easy, different types of starting items are defined according to the service scenes, access specifications are formulated, different service requirements are met, the access cost is reduced, and the starting time is reduced.