Aiming　at　the　problem　of　erect　balance　control　of　hexapod　robot,　a　new　PID　control　algorithm　is　proposed.　Based　on　the　Lagrange　equation　method,　the　erect　equilibrium　state　of　the　hexapod　robot　is　modeled.　For　the　erect　balance　control　problem　of　the　hexapod　robot,　a　quadratic　error　differential　parameter　self-tuning　including　the　secant　saturation　module　is　proposed.　The　simulation　results　verified　that　the　proposed　algorithm　is　feasible,　moreover　compared　with　traditional　method　better　balance　control　performance　can　be　achieved.