A study was conducted for monitoring the insect pests infesting Som plants, Persea bombycina Kost. Planted in the botanical garden of the Department of Life Sciences, Dibrugarh University from February 2018 to June 2018. Altogether 25 genera of insects including 12 natural control agents were recorded by using different trapping methods. Density of Myzus persicae Sulzer and ants on P. bombycina were also evaluated throughout the study. It was found that high degree of correlation existed in between ant density with respect to aphid density. The overall finding showed that the primary host plant of muga silk worm, Antheraea assamensis Helfer though harbors a good numbers of insect pests including gall insect, leaf miner, and stem borer, in the particular study area M. persicae was more abundant and might be acting as a major pest.