A single-stage enthalpy enhancing rotary compressor and an air conditioner having same. The single-stage enthalpy enhancing rotary compressor includes: at least one single-stage cylinder (1), a rotator (2), an upper flange (3), and a lower flange (4). The rotator (2) is arranged inside the cylinder (1) and is rotatable, a compression chamber (10) is formed between the rotator (2) and an inner peripheral wall of the cylinder (1), a vapor injection opening (5) is defined in the upper flange (3) and/or the lower flange (4), and the vapor injection opening (5) is configured to supply gas outside the compressor to the compression chamber (10) directly. According to the present disclosure, two-stage compression is realized without adding an extra cylinder, thereby effectively enhancing a circulation of refrigerant, improving cooling performance of the air conditioner under high environmental temperatures. Moreover, increased power consumption caused by using a two-stage cylinder is reduced, thereby improving energy efficiency of a system effectively, greatly reducing a cost and a power of the compressor, and achieving objectives of high capacity, a high energy efficiency and a low cost.