Bentfin devil ray (Mobula thurstoni) was recorded for the first time in Morotai waters on 3 rd March 2017. In a conservation management context, it is important to clarify the population of Mobula thurstoni and their relations with their habitat. Thus, we examined the existence of Mobula thurstoni with the physical parameters: depth, temperature, visibility, current, weather, and tidal. We measured the existence of Mobula thurstoni with the Underwater Visual Census (UVC) combined with Diver Operated Video (DOV) census. The research from 3 rd March to 14 th July 2017 (50 dives) showed the Frequency of Occurence (FO) is 50% per single dive. The highest aggregation of 30 Mobula thurstoni was recorded at 14 th May 2017 and the average sighting was 3.1 Mobula thurstoni per single dive. Among the examined parameters, it was found that strong factor affecting the sighting of Mobula thurstoni were at the depth of 30-35 m, temperature of 30 C, visibility of 16-20 m, low current (< 1 knot), sunny weather, and tidal category of B. Analysis of UVC and DOV results show that the research location was categorised as feeding location for the Mobula thurstoni.