The study presents for the first time the otolith morphology of nine deep-sea fishes (Polymixia fusca Kotthaus, 1970, Neoepinnula orientalis (Gilchrist & von Bonde 1924), Chlorophthalmus nigromarginatus (Kamohara, 1953), Cubiceps baxteri (McCulloch, 1923), Bembrops caudimacula (Steindachner, 1876), Neoscopelus microchir (Matsubara, 1943), Ostracoberyx dorygenis Fowler, 1934, Synagrops japonicus (Döderlein, 1883), and Bathyclupea hoskynii Alcock 1891). Numerical relationships derived from the relation between size of the otolith and the fish can be used as predictors to estimate the prey size and to understand the trophic relations and food web dynamics of these less studied deep-sea organisms. The study was based on sampling carried out onboard FORV Sagar Sampada (Cruise No 349) during March-April 2016, along the continental margin of the Andaman and Nicobar islands in the Bay of Bengal using high speed demersal trawl. Length–weight relationships (LWR) and the regression between otolith size (width, weight, area and perimeter) and fish length (TL) of nine deep-sea fishes were considered. LWR showed negative allometric otolith growth in five species; four species showed positive allometric growth. Otolith size to fish size (TL) relation is explained by a simple linear regression considering otolith width (OW), otolith weight (OWe), otolith area (OA) and otolith perimeter (OP). Stronger r2 values (>.76) indicate robustness, except for Cubiceps baxteri (r2 = .65), and give better estimates for the TL of the fish.