PURPOSE: A pig for cleaning a pipeline is provided to reduce the scale removal time and improve work efficiency by employing cleaning members capable of being replaced when damaged or abraded. CONSTITUTION: A pig for cleaning a pipeline comprises a seating groove(15) and first and second jacket type cleaning members(16,16a). The seating groove is formed on the outer surface of a pig body(11). The first and second cleaning members are detachably installed on both sides of the seating groove and replaced when damaged or abraded. A wire brush(a) is formed on the outer surface of the first cleaning member, and projections(b) are formed on the outer surface of the second cleaning member.
