In this papet the interaction characteristics between space charge and dipole in the host-guest nonlinear optical polymer electret DR1/PMMA films are studied by means of the open-circuit thermal stimulate discharge(TSD) technique and measurements of the isothermal surface potential decay and the electro-optical effect. The results indicate that there are two kinds of charges：space and dipole in the poled material, the energy level for most of the space charge trapped by the traps of sample is higher than the bound level of dipole charge originating from the dipole alignment after suitable heat than the bound level of dipole charge originating from the dipole alignment after suitable heat treatment, and there is a strong interaction between space charge and dipole. The decay of space charge will cause the change of charge distribution in the materials, which subsequently leads to relaxation of the dipoles. The stability of space charge trapped in the material significantly affects the life of dipole alignment for the material.