How long is a term in Congress?
The term in the House of Representatives is two years and the term in the Senate is six years.
Congress and the Senate are two separate houses, so a Congressmen serves a term in Congress, and a Senator serves in the Senate. A term for a Representative in the House is two years. Senators serve a term of six years. There is no limits on how many terms either officeholder may run for reelection.
It is my opinion that the indefinite times a Congressman can run for election is detrimental to the United States. Long term congressmen tend to take their reelection for granted and long term incumbents are fertile ground for corruption. I believe its healthy for new people to become members of Congress.