When　a　redundant　robot　performs　a　fault-tolerant　operation　for　locked　joint　failures,　its　fault　tolerant　properties　should　include　dexterity　and　sudden　change　of　joint　velocity　at　the　moment　of　locking　failed　joints　and　the　dexterity　during　the　post-failure.　Firstly　three　fault-tolerant　indexes,　reduced　condition　number,　sudden　change　of　relative　joint　velocity　and　centrality　are　proposed,　which　can　comprehensively　evaluate　the　kinematical　performance　of　a　redundant　robot　during　its　entire　fault-tolerant　operations.　Then,　the　influence　of　the　initial　postures　of　robot＇s　end-effector　on　these　fault-tolerant　indexes　is　analyzed　with　a　planar　robot　and　a　spatial　robot.　Simulation　results　show　that　for　a　given　task　the　joint　trajectory　with　the　best　comprehensive　effect　of　fault　tolerance　can　be　determined　by　optimizing　the　initial　posture　of　a　robot.