Paracetamol is an antipyretic drug, when it is taken it reduces the body temperature. So it was thought better to study intermolecular interaction and thus behavior of paracetamol under varied conditions such as temperature, concentration etc. For this certain important physical parameters such as adiabatic compressibility, specific acoustic impedance, relative association, intermolecular free length, relaxation time, free volume, Rao’s constant, Wada’s constant etc. are evaluated using ultrasonic velocity, density and viscosity of paracetamol solution at different concentrations and at 303K.