Aiming at the problem of untimely detection of end-effector chatter during robotic grinding of aeroengine blades, a method of chatter detection based on permutation entropy during grinding is proposed. Using the algorithm for sliding windows to calculate the continuous value of the permutation entropy of the original chatter signal, the empirical threshold of 0.95 for permutation entropy is used to determine whether chatter occurs at the end of the robot. Among them, the algorithm for the permutation entropy based on the ordinal pattern is adopted, which greatly improves the extraction efficiency of the permutation entropy. When the length of the signal is 10000, the computation time of the permutation entropy of the proposed algorithm is reduced to about 0.25 s. And the calculation time of proposed algorithm is reduced by an order of magnitude compared with the traditional algorithm of the permutation entropy. Numerical simulation and experimental results show that the proposed method can detect chatter 0.48 s earlier than the moment of chatter outbreak, which provides more reaction time for taking measures to suppress chatter.