1965-66 Regionalliga season

The 1965-66 Regionalliga season was the fifth season of the Regionalliga (the first to utilize this name), the third level of ice hockey in Germany. 23 teams participated in the league, and EV Rosenheim won the championship.

Southern Group

 * The first-third place teams qualified for the South/Central group of the second round.
 * The fourth-placed team qualified for the 1966-67 Regionalliga Southern group.
 * The fifth-eighth placed teams were relegated to the Bayernliga.

Central Group

 * The first-third placed teams qualified for the South/Central Group of the second round.
 * The fourth-placed team qualified for the 1966-67 Regionalliga Northern Group.
 * The fifth-placed team was relegated to the Hessen regional system.

Northern Group

 * The first-third placed teams qualified for the Northern/Western group of the second round.
 * The fourth-placed team qualified for the 1966-67 Regionalliga Northern Group.
 * The fifth-placed team was relegated.

Western Group

 * The first-third placed teams qualified for the Northern/Western group of the second round.
 * The fourth-placed team qualified for the 1966-67 Regionalliga Northern Group.
 * The fifth-placed team was relegated.

Final round
The first place team qualified for the 1966-67 Oberliga season. The second team qualified for the relegation round to the Oberliga.

2nd place tiebreaker
Kölner EK - EV Pfronten 5:3