In this study, we develop a search-and-matching monetary growth model to analyze the e¤ects of in ‡ation on economic growth and social welfare by introducing endogenous economic growth via capital externality into a two-sector search-and-matching model. We …nd that the channel through which in ‡ation a¤ects economic growth in the search-and-matching model is di¤erent from the traditional cash-in-advance model. To facilitate the calibration, we obtain an empirical estimate of the e¤ects of in ‡ation on economic growth using panel regressions. In the simulation analysis, we quantitatively evaluate the welfare e¤ect of in ‡ation in the search-and-matching endogenous growth model and compare it to a search-and-matching exogenous growth model. We …nd that the welfare e¤ect of in ‡ation is nonlinear in the endogenous growth model whereas it is linear in the exogenous growth model. Furthermore, we …nd that the welfare cost of in ‡ation under endogenous growth is up to four times as large as the welfare cost of in ‡ation under exogenous growth.JEL classi…cation: E41, O41, O42.