No. CNOs need a background in executive administration and business, but a master's in business administration (MBA) or master's in health administration (MHA) is not a prerequisite. But, an MBA or MHA degree can make you a more competitive candidate for a CNO position at larger hospital systems. Some nurses earn an MBA or MHA in preparation for executive leadership positions. An MBA or MHA degree teaches you about accounting, human resource management, financial management, and marketing, which may provide a competitive advantage over other candidates.