To solve the problem that the traditional Loop Closure Detection(LCD)algorithms are unstable and easy to fail in dynamic scenes,an algorithm that can accurately detect the loop closure under dynamic scenes is proposed.First,the algorithm for distinguishing the dynamic from the static features based on the scenes flow is improved so that the dynamic and static points are more accurately determined.Then,the dynamic feature points are removed and clustering processing is performed.The TF-IDF entropy of each node of the image in the visual dictionary tree is used as the weight of the image in the visual word,and a score vector is constructed to describe the scenes.Finally,the negative exponent power function is used as the similarity score function to calculate the similarity scores of the two images.The similarity score between the current frame and the candidate key frame is calculated,and after the final loop closure confirmation,the final key frame forming a loop closure with the current frame is obtained.The experiment of the actual lab scenes shows that the proposed algorithm can effectively detect the loop closure in the dynamic scenes.