The failure analysis of InSb PV detector is studied.With the typical failed products as samples,performance test and device anatomizing were made to find the mechanism of failure. Some problems are found to be the main causes to result in the failures.the problems include:there is reticulation glue remaining on the gold layer;the shapes of lend and gold layer have inadeqnate change that result in invalidat bond;the chip material breaks apart,etc.Failure model was set up and analysis was male.