The　utilization　of　metalens　is　highly　regarded　as　a　promising　solution　for　the　advancement　of　planar　optical　systems　and　is　anticipated　to　find　extensive　applications　in　areas　such　as　near-eye　display.　Ensuring　the　elimination　of　chromatic　aberration　in　metalens　is　imperative　for　their　effective　implementation　in　color　imaging　and　display.　This　paper　proposes　a　novel　design　strategy　for　achromatic　metalens　based　on　regional　dispersion　engineering,　employing　an　algorithm　to　intelligently　select　rectangular　nanostructures　that　can　simultaneously　fulfill　the　phase　requirements　for　correcting　chromatic　aberration　across　different　spectral　bands.　The　results　demonstrate　that　within　the　wavelength　range　of　450-630　nm,　a　vertical　focal　error　of　no　more　than　1.5　mu　m　and　a　focal　length　deviation　of　8.56%　can　be　achieved.　The　average　focusing　efficiency　is　recorded　at　10.27%.　Furthermore,　multi-focal　achromatic　metalens　can　also　be　obtained.　For　demonstration　purposes,　a　dual-focal　achromatic　metalens　(DF-AMLs)　with　vertical　focal　errors　not　exceeding　0.5　mu　m　and　average　focusing　efficiencies　of　6.58%　and　7.96%　respectively　is　achieved.　This　DF-AMLs　holds　significant　promise　for　applications　in　microscopy　and　3D　displays,　providing　new　insights　and　possibilities　for　advancing　related　technologies.