As the lepton number and lepton flavor are conserved quantities in Standard Model, observation of charged lepton flavor violation (cLFV) process will provide clues on beyond-Standard model theories. COMET is an experiment at J-PARC, Japan, which will search for neutrinoless conversion of muons into electrons in the field of a nucleus (μ− + N → e− + N); a lepton flavor violating process. The experimental sensitivity goal for this process is order of 10^−15 for Phase-I and 10^−17 for Phase-II experiment, which is a factor of 100–10000 improvements correspondingly over existing limits. Recent progresses in facility and detector development will be presented, along with COMET Phase-I and Phase-II experimental schedule.