This review discusses the applications of MRI to quantification of the myocardial perfusion. The first step of the measurement is to obtain a concentration-time curve from a signal intensity-time (SI) curve. Factors which influence the correlation between SI and the concentration are discussed for relaxivity and susceptibility agents. The second stage of measurement is to extract parameters of myocardial perfusion from the concentration-time curve. Two methods are considered, one for an intravascular agent and the other for an extravascular agent. Key points are illustrated with experimental data.