Profile of phenolic compounds of Tilia rubra subsp. caucasica was measured by high performance liquid chromatography coupled with ultraviolet and tandem mass spectroscopy. Three different extraction methods (methonolic, selective extraction, and acidic hydrolysis) were used to evaluate phenolic composition and antioxidant capacity in three different parts of T. rubra. The antioxidant activities of the species were investigated in terms of total phenolics and flavonoids, and cupric reducing antioxidant capacity and 1,1-diphenyl-2-picrylhydrazyl scavenging assays. Different phenolic compounds related to antioxidant activities of three different parts and three different extraction ways of T. rubra were determined by high performance liquid chromatography-ultraviolet and high performance liquid chromatography-mass spectroscopy. Gallic and protocatechuic acid were the main phenolic compounds in the all extracts and parts of Tilia rubra subsp. caucasica by high performance liquid chromatography-ultraviolet ranging from 356.20 to 159.83 and 1873.90 to 720.80 g phenolic compound/g dry sample, respectively. Epicatechin, luteolin, and rhamnazin were detected by high performance liquid chromatography-mass spectroscopy.