Abstract
We investigate the phase of two-species bosons in square lattice by the quantum Monte Carlo simulations. The Mott insulator phase becomes solid by increasing the nearest-neighbor repulsion. The phase changing can be driven by increasing the strength of hopping. It is found that there is a direct first-order transition. There is also the transition form the superfluid phase to the supersolid phase by increasing the nearest-neighbor repulsion. And the transition can be found when we drive the strength of hopping. We found that there is a second-order transition.