The invention relates to a device for efficiently and rapidly removing floating oil, in particular to an offshore floating oil collecting device. An oil collecting system comprises a barrel-shaped floating oil collecting device body. An oil conveying pipe penetrates a center axis area of the device body. Ultrasonic transducers are installed at the positions of a left baffle and a right baffle. A metal screen is installed on the barrel surface of the barrel-shaped floating oil collecting device body. Fan blades are installed on the surface of the oil conveying pipe and in the metal screen. The ultrasonic technology is used for emulsifying the floating oil, small oil drops are gathered through an oil conveying hole of a V-shaped structure and are recovered, and the recovery efficiency is higher than that of a film treatment technology.