Michael Gallagher is the name of several different people:

• Michael D. Gallagher is the Assistant Secretary for Commerce and Information in the United States Department of Commerce and Administrator of the National Telecommunications and Information Administration, since 2003.
• Mike Gallagher is a popular conservative radio talk show host and Fox News Channel regular.
• Michael Gallagher (journalist) is an investigative journalist working for Gannett News.
• Michael Gallagher (academic) is a political scientist from Trinity College Dublin, inventor of the Gallagher Index.
• Mike Gallagher (guitarist) is a hard rock guitarist.