In this paper we study composition operators, C φ , acting on the Hardy spaces that have symbol, φ, a universal covering map of the disk onto a finitely connected domain of the form D 0 \{p 1 , · · · , p n }, where D 0 is simply connected and p i , i = 1, . . . , n, are distinct points in the interior of D 0 . We consider, in particular, conditions that determine compactness of such operators and demonstrate a link with the Poincare series of the uniformizing Fuchsian group. We show that C φ is compact if, and only if φ does not have a finite angular derivative at any point of the unit circle, thereby extending the result for univalent and finitely multivalent φ.