The invention discloses an integrating triangular modulating device with matched dynamic elements, comprising an adder, a loop filter and a quantizer, wherein the adder receives an analog input signal and a feedback signal to generate an error signal; the loop filter generates a filtering signal according to the error signal; and the quantizer converts the filtering signal into a quantization output signal. A D/A conversion system comprises a plurality of D/A elements and a dynamic element matching device, wherein the plurality of D/A elements generate a corresponding feedback signal which is equal to the quantization output signal, and the dynamic element matching device receives the quantization output signal, sets one element in the D/A elements as a non-participation element, sets other elements as the participation elements, and selects the participation element corresponding to the quantization output signal according to the quantization output signal and the participation elements. The invention can increase the randomness of selection of the D/A elements corresponding to digital input codes so as to further increase the signal noise distortion ratio.