This invention discloses a test method for double-mode cell phones including tests of a primary platform and a sub-platform, in the test of the primary platform, an instrument simulates a base station to call cell phone by plugging a card in the phone, and when testing the sub-platform, the primary one is at the state of stand-by and the sub-platform calls the instrument to test its parameter by plugging two cards in the phone, which can accurately test the performance parameter of the sub-platform.