The invention relates to a lid comprising a drinking straw which is intended for containers used for drinking liquids and which adapts to the neck of said containers. The inventive lid comprises an assembly of elements, namely: a screw-on lid; a drinking straw conduit which sucks the liquid from the container; a moveable mechanism which opens and closes the passage of liquid; and an air chamber which regulates the release of liquid via a group of valves or regulators. The invention also comprises a protective cover for the aforementioned assembly which is connected to the screw-on lid by means of pressure, by expanding the mouth thereof and fixing it to said screw-on lid by means of internal grip portions which are disposed therein.
