Digital technology is the core driving force of the digital economy. Advancing digital industry clusters （DIC） and accelerating breakthroughs in digital technology innovation （Diginno） are important ways to enhance independent innovation in science and technology and achieve self-reliance in technological strength under the conditions of digital economy. Based on county-level panel data from 2003 to 2021，this paper uses business registration data to measure the development level of DIC and constructed a fixed-effects model to empirically analyze its impact mechanisms and effects on Diginno. The results showed that DIC significantly promotes Diginno，and this conclusion remains robust after a series of robustness tests. DIC mainly promote Diginno through labor pooling，technology spillovers，and sharing of digital intermediate inputs. Heterogeneity analysis indicates that the promotional effect of DIC on Diginno is more significant under conditions of high market potential，favorable business environment，high attention to digital technology，and low competition within counties. Further analysis also revealed that the current DIC in China have a significant positive impact on the TFP of enterprises and the internal resource allocation within industries. However，future attention should focus on the weak empowering effect of digital manufacturing clusters on Diginno as well as the problems of poor quality of county development，unbalanced development and environmental pollution that may result from DIC. This study enriches research on the innovation effects of industrial agglomeration in the digital era. Its core findings will provide important policy implications for further advancing DIC，accelerating scientific and technological innovation，and achieving high-quality development.