Antispin pair annihilation(Abbreviated as APA) gives mechanism for Gravitational jet Baryojet and Oxygen fusion. If pair particles of antiparallel spins collides, they should emit jets to accelerate satisfying the momentum conservation law. Conventional pair model such as Cooper pair of electrons in superconductor, Exciton of electron and hole in the semiconductor, and Pair annihilation of electron and positron in partical physics could be explained in a unifed manner with Antispin pair annihilation.