The phenomenon of migration is known for its multidisciplinary nature and complexities. Here attempt is made to formulate migration model using the concept of physics like Newton’s gravitational law and other laws, involving sophisticated mathematical and statistical tools which will be used later for studying the determinants of interstate migration in India during 1981-1991 and 1991-2001. National census data are the main data available for study of migration. Transition probabilities of interstate migration for fourteen major states in India during 1981-1991 and 1991- 2001 have been estimated. According to probabilities highest inmigrants received states are Maharashtra, Madhya Pradesh, Karnataka Rajasthan and U.P.