Dennis Lawrence "Dan" McGann (July 15, 1871 – December 13, 1910) was an American professional baseball first baseman and second baseman. He played in Major League Baseball (MLB) from 1896 to 1910, and won the World Series in 1905 with the New York Giants. McGann had a troubled personal life. He suffered from depression, and several members of his family committed suicide. After the 1910 season, with rumors of McGann signing with another minor league team, McGann committed suicide with a firearm.