Abstract: The nonlinear acoustic parameter B/A and its dependence on solute concentration have been determined for several aqueous solutions of biological samples by using comparative method. The B/A values for aqueous solutions of dextrose, of sucrose, of ethylene glycol were found tq increase linearly with solution concentration. The B/A value for fresh whole porcine blood has been obtained to be 5.8 at temperature 26℃. Dependence of internal pressure P^* on concentration also has been determined for ethylene glycol solution.