The suspension was announced Monday by the NFL.
According to Aaron Wilson of the Baltimore Sun, the suspension will cost Thompson a total of $112,941, with the loss of four $28,235 game checks out of his 2013 base salary of $480,000.
Thompson played in seven games as a rookie last season before being placed on injured reserve on Nov. 17 with a knee problem.
The 6-foot, 211-pound Thompson will be eligible to return to the Ravens' active roster on the day after the team's fourth regular-season game. He is eligible to participate in all preseason practices and games.
Drafted in the fourth round out of South Carolina State last April, Thompson played in seven of the Ravens' first eight games of the 2012 season. He was a safety in college.
The Associated Press contributed to this report.