There is disclosed a toilet seat transparent elastic cover for preventing a user from a direct contact with a toilet seat. The cover includes mark lines to be aligned ensuring a proper placement of the cover. The cover may include an aperture with two lateral edges and a flap located in front of the aperture. The flap is formed by two lateral perforated lines connecting it to corresponding parts of the cover before the user starts using the cover. The perforated lines are extensions of the two lateral edges, such that when the user places the cover on the toilet seat, tears the perforated lines, and moves the flap forward at a desirable length and downward/upward, the aperture is effectively extended, providing an additional convenience to the user. An objective of the cover is to improve its adjustment to the user's body dimensions correspondingly to typical sizes of the seat.