The 2005–06 Top 14 competition was the 107th French domestic rugby union club competition operated by the Ligue Nationale de Rugby (LNR) and the 1st using the name Top 14.

During the season attendance records in the league were broken with 79,502 spectators attending the Round 9 clash between Stade Français and Toulouse at the Stade de France, shattering the attendance record for any regular league season game in France (not just rugby union).

[1] However, that record was short-lived when 79,604 spectators attended the Round 17 match between Stade Français and Biarritz Olympique.

The semi-finals and final were contested in June, with Biarritz defeating Toulouse to claim back-to-back titles, and their fifth overall.

Two teams were relegated with newly promoted Toulon, who had easily the poorest record in top 14 with just 3 wins from 26 games, being the first to go down, followed by Pau who were much more competitive but not quite good enough to stay up, finishing 3 points from safety.