This study examines the effect of effective tax rate (ETR) and board diversity on the performance of Malaysian public-listed companies (PLCs) in the electric and electronic (E&E) industry. The sample of this study comprised 51 E&E public companies listed in the Main Market of Bursa Malaysia during the financial periods 2018 and 2022. This study documents a significant positive relationship between firm performance and ETR, consistent with the political cost theory, suggesting that high-performing industries such as E&E are more at risk of political scrutiny and, hence, tend to pay higher amounts of tax despite the tax incentives provided by the government. Interestingly, foreign directors are negatively related to a firm’s performance. The possible explanation for this is that the E&E industry is highly regulated by the Malaysian government; hence, foreign directors’ contribution and authority to make independent strategic changes to drive the firm’s performance are limited. Finally, the effect of female directors on firm performance is found to be insignificant, possibly because, on average, only 10% of women are represented on the board of the E&E PLCs. The study findings are of significant interest and beneficial to policymakers, the government, and tax authorities in trying to understand the implications, assess the effectiveness, and tightly monitor the tax incentives and board diversity policy of the E&E companies.