Non-invasive measurement of the intracranial pressure (ICP) via the anterior fontanelle by using an applanation transducer has been performed. Recently, a new fontanometer using an applanation transducer has been developed in our department by improving the conventional Statham transducer, P-50 which is currently accepted for its high reliability. In this study, by analysing patterns of the ICP pulse waves obtained from this new fontanometer, its clinical evaluation has been made in 27 neonates and infants in intracranial pathologies. Analysing the ICP waveforms, the first peak (P1) was divided by the following second peak (P2) and the changes in P1/P2 were examined. A differential amplifier, a dP/dt detector, was also used to make it easier to identify the turning point on the pulse waves. The results obtained demonstrated that the waveforms of ICP in neonates as well as infants are influenced by not only the intracranial constituents but compliance of the container such as the scalp, cranium and the meninges.