CRISPR/Cas9　genome　editing　is　a　promising　therapeutic　technique,　which　makes　precise　and　rapid　gene　editing　technology　possible　on　account　of　its　high　sensitivity　and　efficiency.　CRISPR/Cas9　system　has　been　proved　to　able　to　effectively　disrupt　and　modify　genes,　which　shows　great　potential　for　cancer　treatment.　Current　researches　proves　that　virus　vectors　are　capable　of　effectively　delivering　the　CRISPR/Cas9　system,　but　immunogenicity　and　carcinogenicity　caused　by　virus　transmission　still　trigger　serious　consequences.　Therefore,　the　greatest　challenge　of　CRISPR/Cas9　for　cancer　therapy　lies　on　how　to　deliver　it　to　the　target　tumor　site　safely　and　effectively.　Non-viral　delivery　systems　with　specific　targeting,　high　loading　capacity,　and　low　immune　toxicity　are　more　suitable　than　viral　vectors,　which　limited　by　uncontrollable　side　effects.　Their　medical　advances　and　applications　have　been　widely　concerned.　Herein,　we　present　the　molecule　mechanism　and　different　construction　strategies　of　CRISPR/Cas9　system　for　editing　genes　at　the　beginning　of　this　research.　Subsequently,　several　common　CRISPR/Cas9　non-viral　deliveries　for　cancer　treatment　are　introduced.　Lastly,　based　on　the　main　factors　limiting　the　delivery　efficiency　of　non-viral　vectors　proposed　in　the　existing　researches　and　literature,　we　summarize　and　discuss　the　main　methods　to　solve　these　limitations　in　the　existing　tumor　treatment　system,　aiming　to　introduce　further　optimization　and　innovation　of　the　CRISPR/Cas9　non-viral　delivery　system　suitable　for　cancer　treatment.