The invention relates to an electrostatic separator (1) for separating particles containing oil out of a gas stream, having an emission electrode (2) and a deposition electrode (3), wherein the emission electrode (2) has a front corona region (4) extending into the gas stream and a rear deposition region (5). An outlet opening (9) for separated oil running along the deposition electrode (3) is provided at the level of, or behind, the deposition region (5) of the emission electrode (2).