The objective of this study was to investigate whether board characteristics influence major firm decisions regarding initial public offering and seasoned equity offering and whether industry specialist mitigate the impact of board characteristics on these major decisions. This study conducted an empirical analysis of listed companies in Taiwan from 2013 to 2020. We found that the master’s degrees of the independent directors, number of director training hours, number of director meetings, and director and officer liability insurance influenced the seasoned equity offering decisions that firms made. In contrast, the backgrounds, master’s degrees, and doctoral degrees of the independent directors, the shareholding ratio of the directors and supervisors, number of director training hours, number of director meetings, establishment of audit committees, and director and officer liability insurance influenced the initial public offering of firms. These results show that board characteristics exerted a certain degree of impact on whether firms made major decisions. The inclusion of the industry specialist revealed that the influence of board characteristics on major decisions, whether they involved initial public offerings or seasoned equity offering, were less significant when the auditors were industry specialists than when the auditors were not industry specialists. We speculate that a trade-off relationship may exist between board characteristics and the supervisory function of industry specialization, meaning that when industry specialist have a stronger supervisory mechanism, the need for board supervision becomes less. It is hoped that the empirical findings of this study can provide local empirical evidence regarding the considerations that firms have when choosing board members for major decisions or decide whether to hire an industry specialist auditor.