Embodiments of the present disclosure relate to a digital-to-analog conversion circuit and method, a source driver, and a display apparatus. The digital-to-analog conversion circuit includes a first digital-to-analog converter corresponding to m high bits of (m+n)-bit digital signal and a second digital-to-analog converter corresponding to n low bits, where m and n are integers greater than 0. The first digital-to-analog converter comprises a voltage division module configured to generate 2m reference voltages at equal intervals in voltage; a first voltage selection module configured to select, from the 2m reference voltages, a first voltage corresponding to the m bits; and an operation module configured to generate a second voltage higher than the first voltage by the interval in voltage based on two adjacent reference voltages of the 2m reference voltages and the first voltage. The second digital-to-analog converter is configured to generate a third voltage corresponding to the n bits by using the first voltage and the second voltage as reference voltages, and to generate the sum of the third voltage and the first voltage.