MicroRNAs (miRNAs) have been considered important regulators in both physiological and disease contexts. Among all miRNAs, the miR-34 family (miR-34a, -34b, -34c), which has been well characterized as a tumor suppressor, displays diverse functions in noncancerous diseases. MiR-34 levels are relatively low in the cardiovascular system, but recently they have been reported to function in cardiovascular disorders by regulating apoptosis, telomere attrition, DNA damage, and inflammatory response. In this review, we mainly summarize their roles in cardiac senescence and ischemic diseases.