Based　on　fuzzy　control　theory,　the　joints　position　control　of　2R　underactuated　robot　is　studyed.　a　electromagnetic　brake　is　fixed　into　the　passive　joint　to　control　the　coupling　state　between　joints.　The　process　to　control　the　robot　position　can　be　divided　into　two　phases.　The　brake　is　released　during　the　first　phase.　Depending　on　the　dynamic　coupling　effect　between　the　angle　acceleration　of　passive　joint　and　the　torque　of　active　joint,　passive　joint　can　be　controlled　indirectlly　to　the　desired　position　along　the　desired　trajectory.　The　fuzzy　control　rules　during　the　first　phase　are　described　and　fuzzy　controller　are　designed　to　control　the　motion　of　passive　joint.　The　brake　is　locked　during　the　second　phase,　then　active　joint　is　controlled　to　the　desired　position.　The　experimental　control　system　based　on　PMAC　controller　is　designed　and　developped.　Finally,　the　position　control　of　the　2R　underactuated　robot　is　achieved　successfully　by　experiments.　The　experimental　data　indicates　that　the　fuzzy　control　method　presented　has　high　precision　and　good　robust　character　for　position　control　of　the　passive　joints.　Furthermore,　this　method　doesn＇t　rely　on　the　dynamic　model　of　the　robot　and　the　calculation　during　real-time　control　is　very　few,　which　shows　the　advantage　of　intelligent　control.