This　paper　investigates　the　reliability　and　sensitivity　analysis　for　a　repairablek-out-of-n:Gsystem　with　retrial　of　failed　components.　Such　a　model　has　important　practical　applications　in　fully　automatic　systems,　and　the　most　typical　one　is　fully　automatic　manufacturing　system.　Markov　models　for　availability　and　reliability　of　the　system　whose　components　are　all　subject　to　two　failure　modes　are　presented.　There　is　no　waiting　space　for　failed　components　in　the　system.　If　a　failed　component　finds　the　repairman　busy　and　it　can　not　be　repaired　at　once,　it　will　enter　into　the　retrial　orbit　and　try　again　for　repair　after　some　random　period　of　time.　Some　reliability　indexes,　including　steady-state　availability,　reliability　function　and　mean　time　to　system　first　failure,　are　derived　by　using　vector　Markov　process　and　Laplace　transform　theory.　Sensitivity　analysis　and　relative　sensitivity　analysis　are　provided　as　well.　Finally,　some　numerical　experiments　are　conducted　to　show　the　effects　of　system　parameters　on　the　system　reliability　indexes.