Comparatively large pressure fluctuation of higher order blade frequency (2nd5th) was observed at the full scale container ship. Then, cavitation observation and measurement of fluctuating pressure were performed in the cavitation tunnel by using the propeller model and comparatively large fluctuating pressure of 2nd and 3rd blade frequencies was measured. It was found from the model test that 2nd and 3rd blade frequency components of the fluctuating pressure were caused by the propeller tip vortex cavitation.