The invention provides a method for quickly estimating robust state of a power system. The method is used for dynamically adjusting quantity measuring weight through a factor table increment correction algorithm and includes: step 1, acquiring a Jacobi matrix H of a quantity measuring equation Z of the power system according to a power grid model and data of power transmission section; step 2, performing orthogonal transformation on the Jacobi matrix H to acquire an active iteration upper triangular matrix LP and a reactive iteration upper triangular matrix LQ; step 3, performing active iteration calculation and reactive iteration calculation on the matrixes LP and LQ to acquire a state quantity estimation value and quantity measuring residual; step 4, judging the quantity measuring weight according to the quantity measuring residual sigma, and if weight adjustment is needed, adopting the factor table increment correction algorithm to correct the matrixes LP and LQ and returning back to step 3. Compared with the prior art, the method has the advantages that by combining dynamic weight adjusting technology with the factor table increment correction algorithm, accuracy of state estimation can be improved effectively, and calculating time of state estimation is reduced.