A catheter tip pressure transducer is employed for purposes of measuring fluid pressure within a living body. This includes a tubular housing having a pressure inlet aperture therein. A semiconductor block is carried within the housing and has first and second oppositely facing surfaces, one of which faces the inlet aperture and the other faces in the opposite direction. One of the surfaces has a recess formed therein of such a depth to define an elongated rectangular shaped membrane. A pair of elongated grooves are formed in the nonrecessed surface of the semiconductor block. These grooves are in registry with and straddle the longitudinal side edges of the membrane and define therebetween a raised longitudinally extending central portion in the form of a membrane beam which acts as a free beam supported at its opposite ends by the semiconductor block. Pressure forces acting on the membrane beam result mainly in longitudinally extending deformation of the beam and this is sensed by one or more strain gauges carried by the beam. By this construction, the cross sectional dimensions are optimized so that the transducer may be mounted in catheters and needles of smaller internal diameters.