In　ghost　imaging,　an　illumination　light　is　split　into　test　and　reference　beams　which　pass　through　two　different　optical　systems　respectively　and　an　image　is　constructed　with　the　second-order　correlation　between　the　two　light　beams.　Since　both　light　beams　are　diffracted　when　passing　through　the　optical　systems,　the　spatial　resolution　of　ghost　imaging　is　in　general　lower　than　that　of　a　corresponding　conventional　imaging　system.　When　Gaussian-shaped　light　spots　are　used　to　illuminate　an　object,　randomly　scanning　across　the　object　plane,　in　the　ghost　imaging　scheme,　we　show　that　by　localizing　central　positions　of　the　spots　of　the　reference　light　beam,　the　resolution　can　be　increased　by　a　factor　of　root　2.　same　as　that　of　the　corresponding　conventional　imaging　system.　We　also　find　that　the　resolution　can　be　further　enhanced　by　setting　an　appropriate　threshold　to　the　bucket　measurement　of　ghost　imaging.