Ca-substituted epitaxial YbBa2Cu4O8 (Yb124) films were prepared by a coating-pyrolysis process to enhance the superconducting transition temperature. The Ca-doped Yb124 films showed higher T-c values, e.g., 81K, by AC-susceptibility measurement for the film with a nominal composition of Yb :Ca: Ba: Cu = 0.95 : 0.05: 2: 4. These films contained a small proportion of Ca-doped YbBa2Cu3Oy [Yb(Ca)123] as an impurity phase. However, these high T, values should be attributed not to Yb(Ca)123 but to (Yb1-xCax)Ba2Cu4O8, because both the slow- and fast-cooled films showed almost the same T-c values, that are higher than those of the Ca-free films.