We　investigate　the　quantum　image　matching　algorithm　proposed　by　Jiang　et　al.　(Quantum　Inf　Process　15(　9):　3543-3572,　2016).　Although　the　complexity　of　this　algorithm　is　much　better　than　the　classical　exhaustive　algorithm,　there　may　be　an　error　in　it:　After　matching　the　area　between　two　images,　only　the　pixel　at　the　upper　left　corner　of　the　matched　area　played　part　in　following　steps.　That　is　to　say,　the　paper　only　matched　one　pixel,　instead　of　an　area.　If　more　than　one　pixels　in　the　big　image　are　the　same　as　the　one　at　the　upper　left　corner　of　the　small　image,　the　algorithm　will　randomly　measure　one　of　them,　which　causes　the　error.　In　this　paper,　an　improved　version　is　presented　which　takes　full　advantage　of　the　whole　matched　area　to　locate　a　small　image　in　a　big　image.　The　theoretical　analysis　indicates　that　the　network　complexity　is　higher　than　the　previous　algorithm,　but　it　is　still　far　lower　than　the　classical　algorithm.　Hence,　this　algorithm　is　still　efficient.