The Kimberley Marine Park, located off the coast of north-western Australia, represents a biologically important refuge for marine megafauna, notably humpback whales, dolphins, dugongs, and turtles, amidst extensive coral communities. However, there is very little information available on demersal shark diversity and population estimates. In this study, we directly compared the efficacy of eDNA metabarcoding and conventional longline deployments to survey demersal and pelagic elasmobranchs in the Kimberley Marine Park. Seawater samples were collected for eDNA screening within 12 hours post-longline deployment at 36 sites across a 55,000 square-kilometre area. In total, we recovered 50 elasmobranch taxa, 36 of which were detected by eDNA and 32 (from a total of 815 captured sharks) by longline; a combined approach yielding over 38% more elasmobranch taxa than either approach alone. Site community compositions notably varied between the two survey approaches, but also from broader environmental influences. We additionally investigate whether eDNA metabarcoding read abundance data correlates with longline aggregate catch data and assess required levels of eDNA replication and longline deployments to maximise captured elasmobranch diversity, whilst minimising longline fatalities. This study sets an integrated baseline and long-term monitoring approach for the management and conservation of elasmobranchs within this unique marine park.