The purpose of this study is searching for the top quark decay via flavor changing neutral current. The analyzed data is collected by CMS detector at LHC with 35.9 fb-1 integrated luminosity in pp collisions at √s = 13 TeV. This study will be focused on Top quark-antiquark events, in which one of the top quarks decays to a bottom quark and a W boson, and the other decays to a charm(or up) quark and a Higgs boson, where Higgs decays to two photons. The previous √s = 8 TeV result shows no significant excess in data by comparing the observed and expected diphoton events of t -> qH process. The same strategy will be adopted in this study.