A thick-film cathode was fabricated by a screen-printing technique using LiCoO 2 paste to improve the discharge capacity in lithium-ion micro-batteries. A LiCoO 2 thick film (approximately 6 μm) was formulated by screen-printing using ethyl-cellulose-based paste. As the adhesion force between the printed cathode and substrate was very weak, delamination was observed during the evaporation of a Li anode on a lithium phosphorous oxynitride (LiPON) solid electrolyte. In order to enhance the adhesion force, a small amount of epoxy was added to the ethyl-cellulose-based LiCoO 2 paste. The printed cathode developed in this work showed a typical discharge curve of a LiCoO 2 cathode with a discharge capacity close to the theoretical value when the cell was tested using an organic electrolyte. The assembly of an all-solid-state micro-battery with a stable open-circuit voltage (OCV) free from delamination or electrical problems is possible using LiPON solid electrolyte and Li evaporated onto printed LiCoO 2 cathode thick films. The printed LiCoO 2 thick film was shown to be a potential candidate for cathodes of all-solid-state micro-batteries, despite the fact that a low discharge capacity was obtained in this work.