Abstract: Let-7 family is one of the microRNAs that consists of 21 nucleotides found in C. elegans. Recent research has shown that it plays an important role in regulating the cardiovascular system. Let-7 members are important in the development of heart disease because let-7 is specifically expressed in cardiovascular tissue. So far, TLR4, LOX-1, Bcl-xl and AGO1 are the identified target genes of let-7. Let-7 may be a potential therapeutic target for cardiovascular diseases. This article reviews research progress of microRNA let-7 in cardiovascular diseases.