Our run at Ouda observatory revealed that V4641 Sgr frequently showed "dip"-like variations last night. As reported by Kato-san, the prominent dip occurred around May 23.755 U, and furthermore, the light curve observed at Ouda shows additional dips around 23.717, 23.731, and 23.765 UT. All of them have very sharp profiles and short-term modulations were less prominent during these dips. Some variations were also appeared, except for the dips, but their time-scale was relatively long. Oscillations of sec-time scales were very weak, or disappeared. Regards, MAkoto Uemura