The pest control seal for a recreational vehicle (RV) comprises a relatively soft and resilient foam material, which is compressed into the annular opening between the conduit and a passage through the wall or panel of the service compartment of the RV, and a relatively thin, hard retainer, which is attached to the rim or flange of the hose or conduit opening or passage. The foam material and retainer may be attached to each other, or may be installed as separate pieces held in place by compression and suitable fasteners. The retainer may be formed as two semicircular components, or as a single annular piece.