Abstract: Wooden gutters are protected against the weather and their useful life extended by applying a flexible plastic liner along the trough of the gutter and closing the ends thereof with sealing caps. The liners and caps are tightly secured in place to prevent water from seeping in-between the liner and the wood gutter. The liner is of extruded, flexible plastic material contoured to fit snuggly within the gutter trough and is readily cut to a length corresponding to the length of the gutter. The end caps may be made of injection molded plastic parts formed with cooperating grooves to receive the ends of the liner, and connectors are provided to join adjacent sections of liners. Other components include corner joints, drain connectors and lifters to provide a pitch to the liner to ensure drainage.