Allergic conjunctivitis is the most common syndrome with a prevalence rate of 5– 22%. Diagnosis is difficult due to nonspecific presentation. Various time consuming diagnostic methods are present. Aim of our study is to evaluate that impression cytology is a routine supportive diagnostic tool for allergic conjunctivitis. 110 patients were included in study presenting with ocular itching, tearing, conjunctival hyperemia. Patients were graded as mild (n=32), moderate (n=65), severe (n=13) on basis of DECA^*. Impression cytology of conjunctiva was done. Conjunctival eosinophilia was found in all patients. Several inflammatory cells were found in 71.88% (n=23) mild grade patients and abundant inflammatory cells were found in 100% moderate and severe grade patients. To conclude allergic inflammation and destruction starts early in disease. Impression cytology is a simple, reliable, cost effective, routine supportive diagnostic test to substantiate and document clinical diagnosis and help in treatment.