The present invention relates to a cloud streaming service system, a data compressing method for preventing memory bottlenecking, and a device for same and, particularly, to a technology that: can prevent memory bottlenecking by compressing data when the transmitted amount of original buffer data exceeds a reference value, based on a system memory bandwidth; can provide a cloud streaming service by applying an order of priority by service type according to whether the processing limit, for the number of simultaneous connecting entities that can be processed by one server, is reached during a cloud streaming service; and can test whether a sever that provides a cloud streaming service is operating normally and whether a connection error occurs.