This study aimed at determination of vitamin (A, E, C, β-carotene, and lycopene), phenolic, and flavonoid contents in apricots at different stages of ripening using high-performance liquid chromatography (HPLC). The effect of ripening in terms of phytochemical contents was investigated. Early period apricots showed 2.5 to three times higher level of vitamins (A, E, C, and β-carotene, and lycopene) in all types of apricots than others (P < 0.05). Early-ripened cultivar, Boccuia, showed the highest level of vitamins, although a higher level of vitamin C was measured in late-ripened cultivar Levent (P < 0.05). No lycopenes were determined in late-period apricots in contrary to early- and middle-period apricots. Levels of phenolics and flavonoids were measured in all types (3-B-Q-D, procyanidin B1, B2, B3, caffeic acid, gallic acid, p-coumaric acid, epigallocatechine, catechine, epictechine, chlorogenic acid, ferrulic acid, and routine) and statistical deviation of all types was noted (P < 0.05). Among all, the cultivar Özal showed the highest level of chlorogenic acid (45,843.00 μg·g−1 dry matter) in all ripening periods, where middle-ripened cultivar Adilcevaz showed the lowest level of p-coumaric acid (7.93 μg·g−1 dry matter content base).