The fishing industry is an important contributor to Tonga's economy and food security. Tuna industry is still in a developing stage, the tuna resources occur in 700km2 of Tonga waters. Within this industry the resource of deep swimming tunas accessible to longline gear is dominant by Albacore Tuna (70-80%) therefore it is important to explore how the catches may be vulnerable to climate change. A better understanding is needed of the relationship between Sea surface temperature (SST) and ENSO in the South Western Pacific Ocean and impacts on fish catch in Tongan waters. This study investigates this relationship by utilising SST, ENSO, and Tuna catch data from 2001-2012. The results showed there is not a clear relationship of tuna catches with SST and ENSO in Tongan waters. However, other factors that may account for these variations need to be further investigated, including short dataset, lack of infrastructure eg wharfs, onshore facilities, high cost environment including high fuel prices etc.