Abstract: An apparatus and method for calibrating the pressure readings obtained by catheter tip pressure transducers. The apparatus includes a Plexiglas vessel covered by a closure containing eight catheter ports through which the transducers are introduced into the vessel. The vessel is filled with saline solution that has been warmed to body temperature. The transducer ends of the catheters are inserted through airtight hemostatic control valves into the vessel through the catheter ports. Plexiglas guide tubes are used to guide the transducers into the saline solution at predetermined distances below the surface of the saline solution. The distances are used to calculate the hydrostatic pressures exerted upon the transducers by the saline solution. Known pressures are applied to the transducers through an airtight pressure port in the closure. Calculated hydrostatic pressures are added to the known pressures to provide calibration pressures for comparison with monitored pressure readings.