Partially end-pumped slab laser is an innovative solid laser, namely InnoSlab. Combining the hybrid resonator with partially end-pumping, the output power can be scaled at high beam quality. In this paper, the output near-field and far-field intensity distributions are simulated by coordinate transformation FFT algorithm, comparing the thermal lens effect influence. As the simulated curves showed, the output mode is still good when the thermal lens effect is strong, indicating the good thermal stability of InnoSlab laser. The simulation is very helpful to design and optimize such slab laser.