The method for state estimation based on the measured data of data-acquisition system in electric power system relates to the field of power system analysis technique, characterized in that the method comprises: distributing the said measured data into an operating power system to form a calculation model, defining the injection power of the link nodes as 0 and taking the maximum active power output, maximum reactive power output of the generator as the constraints, constructing a mathematic model for estimation, resolving the optimum solution of the voltage amplitude and voltage phase angle for every node, and calculating the estimated values of the voltage, the active power and the reactive power by using the optimum solution of the state variables, if the difference between the measured value and the estimated value was less than a parameter α that is predetermined under different voltage levels, the estimated value is qualified. The estimation criterion provided by the present invention is unlikely affected by bad data with a strong capability of robust, improving the correctness of the estimation.