A sharp focusing schlieren system gives a means for observing any cross section of a flow field, which is perpendicular to the test beam axis of the optical system. This is impossible for a conventional schlieren system. In this study, a sharp focusing schlieren system was designed with referring to the Weinsten's system to investigate visualization characteristics experimentally. A visualization of butane jet from the 0. 5mm exit diameter nozzle was performed. The results show that the instrument has a capability.for visualizing any cross section of the butane jet.