Abstract: In recent years, spatial impression has received considerable attention in room acoustics, especially in relation to sound quality. Several objective indicators related to spatial impression have been proposed to evaluate acoustic quality in auditoria. To quantify these indicators, the strength and directional distribution of early reflections in the time domain needs to be investigated. The objective of the present work is to develop a measurement system to estimate the direction of early reflections in an enclosure. A method is employed based on transient sound intensity measurement by four arbitrarily configured microphones, which are not placed on the same plane. This approach simplifies the geometric configuration of microphones, therefore facilitates in-situ measurement. The measurement system developed with this method is validated in an experiment carried out in an anechoic chamber while estimating the direction of single incident sound. An example using this method to measure directional distribution of early reflections in a room is also presented.