Heart and kidney interact with each other. Cardio-renal syndrome (CRS) refers to conditions where acute or chronic dysfunction of either the heart or the kidney leads to dysfunction of the other. Conventional classification of CRS outlined five subgroups according to the clinical presentation. This review focused on the epidemiology, new bio- markers, drug management, and renal replacement therapy of type Ⅰ and type Ⅱ CRS, which emphasized the multi-discipline collaboration and individualized evaluation, in order to achieve goal-directed approach to renal replacement therapy.