A set of single chain all-alpha proteins has been examined to determine the contribution of C-H...O interactions to the protein stability. The study of C-H...O contacts is the prerequisite for comprehending the folding processes. There are number of amino acid residues that can form hydrogen bonds via their side chains in addition to their peptide group. Perhaps, the highest contribution in this category is the aromatic residues such as Phe, Tyr and Trp. A total of 1061 C-H...O interactions were found in a data with a set of 75 single chain all-alpha proteins. The most prominent were the side-chain to main-chain C-H...O interactions (SM- C-H...O). The importance of this interaction is revealed by the high degree of conservation observed by them in protein structures. 74% of the stabilizing centers in the single chain all-alpha proteins were involved in C-H...O interactions. These interactions are mainly formed by long range contacts. Moreover, the study shows that there is an average of one C-H...O interaction observed for every 17 residue in the single chain all-alpha proteins data set. It is thus concluded that the C-H...O interaction can, indeed, be categorized as a true stabilizing force like hydrogen bond in single chain all-alpha proteins.