The plasma enhanced chemical vapor deposition (PECVD) method has turned out to be an excellent technique for creating new materials with unique properties that are not obtainable by any other methods. A special place is occupied by materials in the form of very thin films ( < 1 mu m) that reveal catalytic activity for various chemical and electrochemical processes. Such catalytic films open the way for new designs of structured reactors as well as constructions of electrodes for fuel cells and systems for water splitting. In this paper, a brief review of the research conducted in our laboratory on plasma-deposited nanocatalytic films based on cobalt oxides-their production, molecular and nano structure, and catalytic properties-is presented. The main attention is focused on the catalytic activity of the films in such processes as (1) volatile organic compounds (VOCs) combustion, (2) CO2 methanation, (3) CO2 hydration, (4) oxygen reduction reaction (ORR) used in hydrogen fuel cells, and (5) oxygen evolution reaction (OER), which plays a key role in the water splitting process. The wide range of the PECVD method in the production of thin-film nanocatalysts, resulting from the possibility of a wide selection of suitable precursors and the manufacturing process conditions, the co-deposition from two or more precursors, and the preparation of sandwich-like systems, is particularly emphasized.