Lepton flavor violating processes of charged particles (CLFV) are forbidden in the standard model of elementary particle physics. The muon rare decay $\mu \rightarrow e\gamma$ is a CLFV process and has never been observed significantly. On the other hand, in many new theories beyond the standard model, for example supersymmetric grand unification models, the branching ratio of $\mu \rightarrow e\gamma$ is predicted to be around $10^{-14}$--$10^{-12}$, which is experimentally reachable. In year 2013, the MEG experiment has finished its physics-data taking of five years to search for $\mu^{+} \rightarrow e^{+}\gamma$ events with a branching-ratio sensitivity of $~5\times10^{-13}$. Compared to the result published in 2013 by MEG, the full data statistics was doubled by adding data taken in 2012 and 2013 with higher beam intensity. The MEG collaboration plans to upgrade the detector to achieve a ten times better sensitivity. In the conference, a physics result of the MEG experiment and the studies for the upgrade will be presented.