The invention relates to an arrangement and a method for collecting oil from water in open water and/or winter conditions, whereby a vessel's hull and oil collecting equipment are utilized as an oil collector. According to the invention, the oil collecting equipment is attached to the vessel's hull and it is equipped with an auxiliary device, which comprises at least two auxiliary means which are interconnected so that they are movable with respect to each other. The auxiliary means can be utilized in various ways in different conditions.