Abstract: With revised quasi-steady aerodynamic estimation and energy exhaustion methods,the fabric and kinematics parameters of fly-like aircraft were optimized.Firstly,the aerodynamic and energy exhaustion of several example fly-like aircrafts was computed with revised quasi-steady aerodynamic.And then,the minimal energy exhaustion of different flight states and longest flight time together with its optimal kinematics parameters was counted with number inserting approach.The result is as follows: 1) Fly-like aerodynamic structure is more preferable to aircraft with size of several centimeters and millimeters,but its capacity is not superior to routine structure when its wingspan is more than 3.75 centimeters.2) The optimal kinematics parameters of fly-like aircraft are: the rotation is symmetric and its duration of flip is 0.2T～0.25T;acceleration and deceleration duration of stroke is 0.15T～0.2T;mid-stroke angle of attack is 25～30 degrees;the stroke amplitude should be greater when possible,and only when current frequency couldn’t render adequate lifting force can the stroke amplitude be advisably reduced for augmenting the frequency.