<p>The present invention relates to a pipe painting apparatus including a slip ring unit. The present invention includes: a spraying unit which rotates and sprays pints inside a pipe; the slip ring unit having an outer ring which inflows air supplied from the outside and an inner ring which flows air to the spraying unit; a head unit having a paint transfer unit which flows paint to the spraying unit; and a driving unit which is connected to the head unit and is formed to be movable for a pipe inner surface. The present invention provides the pipe painting apparatus for efficiently flowing the paint and air to the spraying unit.</p>
