This study was conducted primarily to determine fish diversity of the coastal waters of mining areas in Tubay, Agusan del Norte. There were 23 fish species identified belonging to 19 genera and 12 families. Indo-pacific sergeant fish (Abudefduf vaigiensis) was relatively the most abundant in all the three stations comprising more than 25% of the total. Station 1 had the most numerous (556) and diverse (1.969) fish species. There was a significant difference in the number of fish individuals but had no significant difference on species diversity index with respect to sampling stations. Station 2 had the highest species richness index (0.633), while Station 3 had the most even distribution (0.817). Stations 1 and 2 were 77.8% similar. The average water depth, temperature, transparency, pH and salinity were 4.52 meters, 26.53 ºC, 3.97 meters, 8 and 34.33 ppt, respectively. These all fall within the DENR standards for Class SC water.