The　outbreak　of　Corona　Virus　Disease　2019　(COVID-19)　has　affected　the　lives　of　people　all　over　the　world.　It　is　particularly　urgent　and　important　to　analyze　the　epidemic　spreading　law　and　support　the　implementation　of　epidemic　prevention　measures.　It　is　found　that　there　is　a　moderate　to　high　correlations　between　the　number　of　newly　diagnosed　cases　per　day　and　temperature　and　relative　humidity　in　countries　with　more　than　10,000　confirmed　cases　worldwide.　In　this　paper,　the　correlation　between　temperature/relative　humidity　and　the　number　of　newly　diagnosed　cases　is　obvious.　Governments　can　adjust　the　epidemic　prevention　measures　according　to　climate　change,　which　will　more　effectively　control　the　spread　of　COVID-19.