A system status control method and a portable terminal are described. The portable terminal includes a first system with a first interface and a second system with a second interface, and the first system and the second system are joined or separated through the first interface and the second interface. The method includes when the first system and the second system enter a joined-up status from a separated status, the first system and the second system exchanging respective system status information thereof; and the first system and the second system control the system status according to the system status information and based on a preset policy. When a master system and a slave system are combined or separated, automatic switch control may be performed on the system status according to a usage requirement of a user and based on the preset policy.