The 2015–16 División de Honor was the 49th season of the top flight of the Spanish domestic rugby union competition since its inception in 1953. Regular season began on 19 September 2015 and finished on 1 May 2016.
The playoffs began in May, with the Final taking place on 28 May.
The season took place between September and March, with every team playing each other home and away for a total of 22 matches. Points were awarded according to the following:
4 points for a win
2 points for a draw
1 bonus point for a team scoring 4 tries or more in a match
1 bonus point for a team that loses a match by 7 points or fewer
The six teams with the highest number of points at the end of 22 rounds of matches played the championship playoffs. The top two teams win a semifinal berth automatically, while the next four teams played off to take the remaining two spots.
The club which finished bottom was relegated, while the club that finished 11th went into a playoff with a team from División de Honor B.
Promotion and relegation
The bottom team in the standings was relegated to División de Honor B, while the team finishing 11th played the relegation playoff. The top team from División de Honor B was promoted to División de Honor.
The relegation playoff was played over two legs by Bizkaia Gernika, the team finishing 11th in División de Honor, and CAU Valencia, the losing team from División de Honor B promotion playoff final. Bizkaia Gernika won 129–25 on aggregate and remained in División de Honor for 2016–17 season.