| Year: | 1978 |
| Gender: | men's |
| Division: | Division II |
| Teams: | 4 |
| Frozenfourarena: | American International College |
| Frozenfourcity: | Springfield, Massachusetts |
| Champions: | Merrimack Warriors |
| Titlecount: | 1st |
| Champgamecount: | 1st |
| Champffcount: | 1st |
| Runnerup: | Lake Forest Foresters |
| Gamecount: | 1st |
| Runnerffcount: | 1st |
| Semifinal1: | Mankato State Mavericks |
| Frozenfourcount: | 1st |
| Semifinal2: | Elmira Soaring Eagles |
| Frozenfourcount2: | 1st |
| Coach: | J. Thom Lawler |
| Coachcount: | 1st |
| Mop: | Jim Toomey |
| Mopteam: | Merrimack |
| Attendance: | 2,409 |
The 1978 NCAA Men's Division II Ice Hockey Tournament involved 4 schools playing in single-elimination play to determine the national champion of men's NCAA Division II college ice hockey. A total of 4 games were played, hosted by American International College.
Merrimack, coached by Thom Lawler, won the national title with a 12–2 victory in the final game over Lake Forest.
Jim Toomey, of Merrimack, was named the Most Outstanding Player and was the high scorer of the tournament with seven points (1 goal, 6 assists).
Due to the lack of conferences and tournaments for western schools the NCAA held a regional tournament to help select teams for the national tournament. The western regional tournament is not considered as part of the NCAA championship but is included here for reference. No automatic bids were offered.
| Team | Record | |
|---|---|---|
| Elmira | 26–4–0 | |
| Lake Forest | 22–4–0 | |
| Merrimack | 19–9–2 | |
| Mankato State | 16–15–1 |
Note: * denotes overtime period(s)