An electrostatic collection device of particles in suspension in a gas including a collecting chamber with a collecting wall, part of which forms a collecting electrode. The collecting electrode faces a discharge electrode in the form of a wire, so as to create a corona discharge between the discharge electrode and the collecting electrode, the collecting wall extends to the periphery of the discharge electrode. The discharge electrode is maintained at a first end by a first holder and at the second end by a second holder, both holders made of electrically insulating material(s). At least one traversal wall protrudes from the collecting wall, and has a shape adapted to deflect the path of a liquid present in the gas and flowing on the collecting wall to the transversal wall such that it does not come into contact with the second holder.