The invention provides an electric seat adjusting method and system and a vehicle. The electric seat adjusting method includes the steps that a current adjusting mode of an electric seat is collected, and adjusting modes include the high-speed / long-distance mode, the congestion / downtown mode, the rugged / bumpy mode, the ramp mode and the automatic mode; current state values of preset parameters used for representing a vehicle state are collected; the current state values are compared with a seat state value range of the current adjusting mode to obtain a comparison result; according to the comparison result, when the current state values are in the seat state value range, corresponding correction of current moment is obtained; the correction of the current moment is processed to obtain a result value; the electric seat is adjusted according to the result value. According to the provided scheme, the posture of the electric seat is automatically corrected, the adjusted seat enables a driver to be in a more comfortable and safer sitting posture appropriately, and the problem that because traffic conditions of roads are complex, the driver is fatigued and discomforted to cause misoperation is solved.