The Mayor of San Diego serves as the chief executive officer of the city, overseeing all city services, policing, policies, and the enforcement of laws and ordinances within the city limits. The mayor's responsibilities include proposing a budget, signing legislation into law, appointing department heads and members to city boards and commissions, and overseeing the city's day-to-day operations. The Mayor also represents the city on the state, national, and international stage.

San Diego operates under a "strong mayor" system, which gives the Mayor a position similar to that of a corporate CEO, separate from the City Council, and with veto power over Council decisions. This system was voted into place in 2004, as a change from the previous "council-manager" system where the Mayor was more of a figurehead with the City Manager running the day-to-day operations.

Recent holders of the office have grappled with issues ranging from economic development, homelessness, public safety, and the city's infrastructure. Each mayor brings their priorities and management style to the role, shaping the city's direction and policies. For example, Kevin Faulconer, who served from 2014 to 2020, focused on economic growth, reducing homelessness, and improving city services. His tenure saw efforts to expand the convention center, initiatives to address the city's housing crisis, and the expansion of environmental programs.

Notable officeholders include Maureen O'Connor (1986-1992), San Diego's first female mayor and Roger Hedgecock (1983-1985), whose term was cut short by legal issues but who went on to have a long career in broadcasting. Additionally, Pete Wilson, who served as Mayor from 1971 to 1983 before moving on to the United States Senate and then serving as Governor of California, is among the city's most high-profile political figures.

The Mayor's position is nonpartisan, reflecting San Diego's status as a charter city in California, meaning that elections for the office are conducted without formal party affiliation. This nonpartisan approach is designed to focus on local issues and governance rather than national party politics.