Biodiversity is defined as the variety of life. In agricultural system, biodiversity refers to estimation of number of species that are present in that ecosystem. In an interrelated ecosystem, different species of insects perform different functions; act as pollinators, recycle nutrients, water and energy in many ways. In this kind of mutually dependent systems, the loss of even single species can affect the entire system very severely. Therefore, diversity estimation of insects help in conservation of insect fauna and stabilization of ecosystem. Present study focused on estimation of diversity and also the relative abundances of insect fauna associated with Trifolium alexandrinum (Berseem) in District Sialkot. Total of six orders such as, Orthoptera, Hemiptera, Lepidoptera, Diptera, Hymenoptera and Coleoptera belonging to 12 families i.e., Acrididae, Gryllidae, Aleyrodidae, Pentatomidae, Noctuidae, Syrphidae, Culicidae, Formicidae, Braconidae, Coccinellidae, Staphylinidae and Chrysomelidae were sampled from district Sialkot. Coleoptera was recorded as most abundant order with 39% relative abundance. By statistical analysis significant difference (p-value< 0.005) was found in presence of diversity in different months of sampling. Shannon index was maximum in the month of May (H’=2.819). Canonical Corresponding Analysis (CCA) determines the impact of different environmental factors on presence of different species.