Integrated microcavity comb technology exploits optical nonlinearity within integrated microcavities to generate periodic optical pulses under continuous optical pumping. These pulses exhibit equidistant optical-frequency components in the frequency domain. Compared to traditional optical combs, integrated microcavity optical combs offer advantages such as miniaturization, low power consumption, and high repetition rates. Their unique time-frequency characteristics not only facilitate the evolution of traditional optical combs toward on-chip integration but also enable integration with wavelength division multiplexing technology to advance on-chip parallelization, high-capacity information transmission, processing, and sensing. In the generation of microcavity combs, the dispersion of microcavities—i.e., the difference in the group velocity of light at different wavelengths within the cavity—is crucial. Different application requirements necessitate specific cavity dispersion designs. This article reviews the research progress on how dispersion influences optical comb states, discusses recent advancements in integrated microcavity dispersion design, and summarizes current technologies and challenges while looking forward to future developments.