The Fijians topped their pool before beating Old Techs in the semi-final and then Saltash in the final.
In a good final, they triumphed 26-17, having been 14-7 up at half-time.
Saltash had reached the final by topping their pool and then beating Devonport Services in the semis.
Plymstock Albion Oaks won the plate competition. They finished third in their pool behind Saltash and Old Techs and then beat Saltash II in the plate semi-final before overcoming Tamar Saracens 33-7 in the final. Tamar Saracens had overcome Old Techs II in the plate semi-finals.
The annual event attracted 13 teams this year and was played in perfect conditions.