To　address　coupling　motion　issues　and　realize　large　constant　force　range　of　microgrippers,　we　present　a　serial　two-degree-of-freedom　compliant　constant　forcemicrogripper　(CCFMG)　in　this　paper.　To　realize　a　large　output　displacement　in　a　compact　structure,　Scott-Russell　displacement　amplification　mechanisms,　bridge-type　displacement　amplification　mechanisms,　and　lever　amplification　mechanisms　are　combined　to　compensate　stroke　of　piezoelectric　actuators.　In　addition,　constant　force　modules　are　utilized　to　achieve　a　constant　force　output.　We　investigated　CCFMG＇s　performances　by　means　of　pseudo-rigid　body　models　and　finite　element　analysis.　Simulation　results　show　that　the　proposed　CCFMG　has　a　stroke　of　781.34　mu　m　in　the　X-direction　and　a　stroke　of　258.05　mu　m　in　the　Ydirection,　and　the　decoupling　rates　in　two　directions　are　1.1%　and　0.9%,　respectively.　The　average　output　constant　force　of　the　clamp　is　37.49N.　The　amplification　ratios　of　the　bridge-type　amplifier　and　the　Scott-Russell　amplifier　are　7.02　and　3,　respectively.　Through　finite　element　analysis-based　optimization,　the　constant　force　stroke　of　CCFMG　is　increased　from　the　initial　1.6　to　3　mm.