Abstract: Actinomycetes and Histamine Producing Bacteria (HPB) were isolated and identified from the Indian mackerel fish, Rastrelliger kanagurta from three different parts viz., skin with muscle, gills and gut. Among the three parts, gill harboured the highest number of actinomycetes (2.9x105 cfu g-1) and HPB (2.47x105 cfu g-1) than the other parts. At the same time, the fish harboured more number of actinomycetes than HPB. During the present investigation, a total of 29 HPB strains were isolated and identified as Bacillus sp., Pseudomonas sp., Vibrio sp. and Aeromonas sp. Among them, Pseudomonas sp. contributed more (45%) followed by Vibrio sp. (22%), Bacillus sp. (20%) and Aeromonas sp. (13%) in all the three parts of fish. In the present investigation, 41 strains of actinomycetes also isolated and all belonged to the genus, Streptomyces. Out of these 41 strains, 32 strains showed inhibitory activity to one or more HPB at varying levels. Among them, 3 strains viz., ASP-2, ASP-11 and ASP-15 showed good inhibitory activity against all 4 HPB and these 3 actinomycete strains (ASP-2, ASP-11 and ASP-15) were tentatively identified as S. aureofasciculus (ASP-2), S. chattanoogenesis (ASP-11) and S. hawaiiensis (ASP-15). The study indicates that the actinomycetes could be used to control HPB.