The Baltimore Sun is the U.S. state of Maryland’s largest general circulation daily newspaper and provides coverage of local and regional news, events, issues, people, and industries. The Sun was founded on May 17, 1837, by printer Arunah Shepherdson Abell and two associates. The Abell family owned the paper through 1910, when the Black family gained a controlling interest. The paper was sold in 1986 to the Times-Mirror Company of Los Angeles. The same week, the rival Baltimore News American, owned by the Hearst Corporation, announced it would fold. The Sun, like most legacy newspapers in the United States, has suffered a number of setbacks of late, including a decline in readership, a shrinking newsroom, and competition from a new free daily, The Baltimore Examiner, which has since folded. In 2000, the Times-Mirror company was purchased by the Tribune Company, of Chicago.

On September 19, 2005, and again on August 24, 2008, The Baltimore Sun introduced new layout designs. Its circulation as of 2007 was 232,360 for the daily edition and 372,970 on Sundays. On April 29, 2009, the Tribune Company announced that it would lay off 61 of the 205 staff members in the Sun newsroom.

The Baltimore Sun is part of the Baltimore Sun Media Group, which also produces b free daily and more than 30 other Baltimore metropolitan-area community newspapers, magazines and Web sites. BSMG content reaches more than 1 million Baltimore-area readers each week and is the region's most widely read source of news.