Abstract: In order to explore the tea production potential of wild ancient tea trees in Xi’ning town, Leibo county and promote the development and utilization of germplasm resources, the sensory quality evaluation and biochemical composition determination of black tea samples made from the wild ancient tea trees in Xi’ning （referred to as XNBT for short） were carried out, and compared with other black tea samples. The results showed that: （1） XNBT was heavy and firm in appearance, orange-red and bright in soup color, long-lasting sweet with caramel in aroma, sweet, mellow and fresh in taste, and red and soft in phyllotaxis. The sensory evaluation score of XNBT was 90.4, which was slightly higher than that of the black tea made from the spring tips of the clonal tea variety ‘Fuding Dabai’ （90.3, referred to as FDBT） and a commercially available wild-plant black tea in the market （85.5, referred to as CWBT）. （2） The total catechin content of XNBT was 11.5 mg·g⁻¹, which was 40.2% and 30.7% higher than that of CWBT and FDBT, respectively. The caffeine content （48.7 mg·g⁻¹） and total free amino acid content （19.89 mg·g⁻¹） of XNBT were slightly higher than those of the other two black teas. The main tea pigments （thearubigen, theaflavin and theafucin） of XNBT black tea were 131.90 mg·g⁻¹, which was higher than that of FDBT but lower than that of CWBT. In summary, the quality of XNBT was superior and it was valuable for development and utilization. Its quality formation may be related to the biological characteristics of wild tea population and the climate of Leibo. It is recommended to strengthen the protection and utilization of this resource.