In view of the problem that the back-end optimaziation for conventional incremental Graph SLAM alrgorithm cannot efficiently remove the influence of false close-loop,R-iSAM,a robust close-loop incremental Graph SLAM algorithm is put forward based on iSAM algorithm and SC algorithm.In the incremental process,R-iSAM makes a preliminary approximate calculation of the close-loop constrained conversion variables introduced at the current time,obtaining reasonable node positions of robot.In the off-line process,it makes a refined calculation of all close-loop constrained conversion variables in the current period,to judge the correctness of current-period close-loop,and lay a foundation for node optimization later on.The algorithm experiment of public data set (DS) show that under the condition of adding different types and numbers of fault close-loops,the proposed algorithm is well adaptive to different DS,and the convergence rate satisfies the real-time requirement of incremental SLAM,proving the validity of this algorithm.