Although Ariidae are an important group of the aquatic animals in Persian Gulf and Oman Sea waters, they were considered as discarded fishing by the past few years in Iran. Unlike to other countries, they are commercially of low importance and are almost not edible in Iran. In order to collect samples of this group of fish, the research ship Ferdows I, a stern trawler, and a trawler net were used on the seabed. The area under study was that part of Oman Sea bordering with Sistan-o-Baluchistan, starting from Meydani over to the farthest eastern coastal city in the province, i.e. Guatre. The strata under study were 10-20 m, 20-30m, 30-50m, and 50-100m deep. The province’s waters were generally divided into 5 primary strata (M, N, O, P, Q), each of which was divided into 4 sub-strata deep into the water. The sub-strata were all divided into 1-4 nautical square miles (nm²), using maps provided by the geographical office of the army. The biomass of Ariidae belonging to each of the five primary strata is as follows: In the primary stratum O (i.e. the waters of Gurdiom, Pozom, and Konarak) reached its maximum, that is, 1 kg/nm². In the primary strata M and N, it increased progressively, in the primary stratum Q it started to decrease until it eventually reached zero, and in the primary stratum Q it decreased insignificantly. The amount of Catch Per Unit of Area/Ariidae (CPUA) as belonging to each primary stratum indicates that CPUA for the primary stratum O has reached its peak, i.e. 2 kg/nm², and as regards the amount of Catch Per Unit of Area/Ariidae for either of the four sub-strata, CPUA reaches its high in the 10-20 m sub-stratum, that is, 239.2 kg/nm². The average CPUA for Arius dussumieri at a depth of 20-30 m reaches its highest point (6345 kg/nm²), the average amounts to 4231 kg for Arius thalassinus, and for other Ariidae it comes to 7542 kg/nm². Such variations in CPUA indicates that the distribution of Ariidae was mostly observed in coastal waters and rarely at depths greater than 50 m, and that Pozom and Konarak are the most important fishing zones of the Ariidae family.