The study examines the effect of board gender composition on firm market value by employing sample listed non-finance firms on the floor of the Nigerian Exchange Group Market and Nairobi Stock Exchange from 2012 to 2021. Board gender diversity (BOGD) and CEO gender (CEOG) are the board gender composition proxies employed in this study. The study proxies the dependent variable of market value in terms of economic value added (EVAA). Furthermore, in line with related extant literature, this study controls the model goodness of fits by employing the variable of leverage (DETA). The population of this study was made up of 154 non-finance firms listed on the floor of the Nigerian Exchange Group (NGX) and Nairobi Stock Exchange (NSE) as at December 31st, 2022. The sample size for this study consists of 74 listed non-finance firms in Nigeria and 25 listed non-finance firms in Kenya. These firms were selected using the purposive sampling technique. Overall, the empirical findings of this study are mixed in proving the effect of board gender composition on market value in Nigeria and Kenya. Specifically, the study concludes that board gender diversity insignificantly reduces market value and CEO gender insignificantly improves market value of listed non-finance firms in Nigeria and Kenya during the period under study. Generally, the study recommends that there is a need for an improved level of diversity of the board of directors of quoted firms in Nigeria and Kenya that can improve the decision-making process needed for sustainable market value. This can be done by putting into consideration the professional qualification, personality, experience and individual perception towards leadership when forming the board of directors to ensure efficient and effective complex and relevant decision making for higher profitability and performance.