Using Nigeria and Ghana as case studies, this thesis looks at how currency devaluation affects inflation and economic growth in West African countries. Using Auto Regressive Distributed Lag (ARDL) models and annual time series data from 1990 to 2023, the study looks at both short- and long-term impacts of exchange rate fluctuations on macroeconomic stability. Three theoretical frameworks form the basis of the study: the elasticity approach, the monetary approach, and structuralist theory. The empirical results show different effects in the two countries. While devaluation has little direct impact on inflation or GDP, interest rate policy mostly drives inflation in Nigeria. By contrast, Ghana shows a significant inflationary reaction to devaluation of the currency; foreign reserves are crucial in controlling inflation and helping GDP growth. Error correction terms suggest that both economies relatively quickly adjust towards equilibrium, although Ghana shows a quicker and more consistent adjustment mechanism. These findings imply that macroeconomic stability or growth is not guaranteed by currency devaluation by itself. Outcomes, rather, much rely on structural circumstances, institutional systems, and complementary policy actions. The thesis finds that although devaluation can be a short-term adjustment tool, its impact in West Africa is still rather constrained without more structural changes.