Using　thulium-doped　fiber　laser　to　pump　fluoride　fiber　is　one　of　the　most　common　methods　to　generate　mid-　infrared　supercontinuum　(SC).　But　it　is　difficult　to　generate　SC　spectrum　with　wavelength　more　than　4　mu　m　by　directly　pumping　short　fluoride　fiber　with　2　mu　m　picosecond　(ps)　laser.　Although　some　studies　with　SC　exceeding　4　mu　m　have　also　been　reported,　the　proportion　of　spectral　power　in　the　long-wavelength　region　is　not　very　high.　To　address　this　issue,　a　novel　and　simple　approach　to　solve　low　peak　power　of　2　mu　m　ps　pump　sources　is　introduced　by　adding　a　short　piece　of　holmium-doped　fiber.　This　method　can　make　full　use　of　the　gain　bandwidth　of　Ho3+　and　soliton　self-frequency　shift　effect　to　enhance　soliton　energy　and　promote　spectral　broadening.　The　effectiveness　of　the　approach　is　verified　by　constructing　a　theoretical　model　to　solve　the　generalized　nonlinear　Schrodinger　equation.　We　demonstrate　through　simulations　that　addition　of　holmium-doped　fiber　can　yield　significantly　improved　output　spectral　range,　power　ratio　in　the　long-wavelength　region　and　optical-optical　conversion　efficiency　compared　to　the　previous　technical.　Especially,　the　implementation　of　the　new　technology　can　effectively　expand　the　SC　long-wavelength　edge　by　similar　to　470　nm　after　applying　a　3　dB　gain,　and　can　easily　build　a　simple,　compact　and　low-cost　mid-infrared　light　source　system.