High-performance liquid chromatography (HPLC) is a leading technique used for quantitative analysis. Potential applications of a novel porous disperse diamond (PDD) phase in HPLC have been studied. This phase has shown the best separation characteristics in pure water. The PDD column mainly separates components via hydrogen bonding and weaker hydrophobic interactions. Being superior to any other stationary phase in mechanical strength and being chemically stable within a wide range of pH, porous diamonds have interesting potential for use in HPLC.