The correcting performance on piston aberration of beams with adaptive optics-active segmented mirror in laser coherent combining is studied. The piston aberration is introduced by active segmented mirror drived by high voltage which is produced by signal generator and amplified by high voltage amplifier. The far-field pattern with piston aberration is detected by high-speed CCD and the CCD data is processed by digital circuit to produce the close-loop voltage for correcting the introduced piston perturbation in real-time. This experiment performs close-loop correction in different piston perturbation. The experimental results show that the piston perturbation frequency of 50 Hz is efficiently controlled. System also can compensate the piston aberration above one wavelength and combining efficiency reaches 75%.