The invention discloses a high-efficiency multifunctional power tiller which comprises an engine, a driving shaft, a reducer, a front wheel, a rack, a rotary blade shaft, a steering mechanism, a rear wheel, a wheel driving mechanism and a rotary blade group lifting mechanism, wherein the engine transfers power to the reducer through the driving shaft, and the driving shaft drives the rotary blade shaft to rotate through a rotary tillage driving component. According to the invention, the bottom of the rack is provided with a front wheel driving shaft, a rear wheel driving shaft and the rotary blade shaft, the rotary blade shaft and the rear wheel driving shaft are separate, the rear wheel is arranged on the rear wheel driving shaft, and four wheels are driven to walk when the power tiller is operated; the rotary blade shaft only drives a rotary blade blade, the whole power tiller keeps balance through four road wheels, a manipulator does not need to use force to maintain the balance of the whole power tiller, the operation is portable, the time is saved, the labour is saved, and old men and women can operate the high-efficiency multifunctional power tiller; and the whole power tiller walking, the whole power tiller turning and the rotary tillage operation can be used for realizing a machinery automatic combination process, the farming efficiency is high, and the farming effect is good.