Water content in zeolites has been determined by an improved neutron reflection method using a Pu-Be neutron source of 106 n·s–1 intensity and a BF3 counter. It was found that the water content of different types of zeolites collected in Hungary varies between 9 and 12 wt.%. The standard deviation of the determination does not exceed 0.5 wt.%. The matrix effect on the sensitivity and accuracy was also studied. An approximate relation is given between the count rate and the neutron physical parameters of the samples.