With the development of coronary angiography technology, coronary microvascular disease (CMVD) has attracted more and more attention. In recent years, it has been found that most patients with CMVD have poor prognosis, so the detection of CMVD is particularly important. Any cause of CMVD will lead to a decrease in coronary flow reserve (CFR), so the measurement of CFR can be used as an important examination method to diagnose CMVD. This paper will review the research progress of CFR and CMVD.