A　jumping　leg　with　one　degree　of　freedom　(DOF)　is　characterized　by　high　rigidity　and　simple　control.　However,　robots　are　prone　to　motion　failure　because　they　might　tip　over　during　the　jumping　process　due　to　reduced　mechanism　flexibility.　Mechanism　design,　configuration　optimization,　and　experimentation　were　conducted　in　this　study　to　achieve　jumping　stability　for　a　bioinspired　robot.　With　locusts　as　the　imitated　object,　a　one-DOF　jumping　leg　mechanism　was　designed　taking　Stephenson-type　six-bar　mechanism　as　reference,　and　kinematic　and　dynamic　models　were　established.　The　rotation　angle　of　the　trunk　and　the　total　inertia　moment　were　used　as　stability　criteria,　and　the　sensitivity　of　different　links　to　the　target　was　analyzed　in　detail.　With　high-sensitivity　link　lengths　as　the　optimization　parameters,　a　configuration　optimization　method　based　on　the　particle　swarm　optimization　algorithm　was　proposed　in　consideration　of　the　different　constraint　conditions　of　the　jumping　leg　mechanism.　Optimization　results　show　that　this　method　can　considerably　improve　optimization　efficiency.　A　prototype　of　the　robot　was　developed,　and　the　experiment　showed　that　the　optimized　trunk　rotation　angle　and　total　inertia　moment　were　within　a　small　range　and　can　thus　meet　the　requirements　of　jumping　stability.　This　work　provides　a　reference　for　the　design　of　jumping　and　legged　robots.