Laser holds a higher output power when working in high-order-mode than working in fundamental mode, coherent combining of high-order mode lasers is a promising way for higher output power. For the inside 0-π phase difference of the wave front, the beam quantity of the high-order mode is not as good as that of the fundamental mode, therefore the brightness of the coherent combining is limited. Coherent combining of high-order mode lasers with wave front compensation is proposed. Inside 0-π phase differences of high-order mode laser are compensated using beam cleanup technology firstly, and then coherent combining is implementing with the wave front compensated lasers. Results of simulation and experiment of inside wave front compensation using optimal algorithm based beam cleanup technology are given. Numerical simulation of coherent combining of high-order Hermite-Guass mode lasers with and without inside wave front compensation is done. Result shows that the power in bucket of one time diffraction limitation of the combining beams with inside wave front compensation is at least 10 times or even more than 1000 times of that value of the combining beams without inside wave front compensation.