Abstract: Investigations were conducted to record the incidence of viruses in apple orchards of the state along with serological detection by employing ELISA. Seventeen apple orchards surveyed in Shimla, Kinnaur and Kullu district of HP revealed the presence of viral infection with an incidence ranging from 5.41-92.18%. Direct Double Antibody Sandwich (DAS ) ELISA assays resulted in detection of ACLSV, ApMV, ASGV and ASPV in apple trees of different commercial cultivars being grown in different orchards. The ACLSV, ApMV, ASGV and ASPV were found to be present in serologically detectable limit in leaves, bark and petals parts of an infected plant. However, leaf sample drawn during April and May, bark during August and petals taken during April found to contain highest relative concentration of these viruses based on the OD values obtained in serological reactions. About 50% of the diseased plants revealed the presence of two or more than two viruses, thus indicating prevalence of mixed infection.