The author reviewed the general principle in the use of psychotropics for patients with renal diseases. who have psychiatric problems. Durgs which are dialyzable and metabolized or eliminated by kidney should not be used for patients with renal failure. However, lithium can be effectively used in a single dose$(300{sim}600 mg/day)$ after each dialysis. though lithium has the double negative components. It is recommended that serum lithium level should be frequently monitored and the dose of lithium should be gradually increased to minimize its side effect Most of other psychotropics such as benzodiazepine anxiolytics tricyclic or tetracyclic antidepressants, and neuroleptics are metabolized in the liver, and they can be used in renal patients. The dose of these drugs should be reduced in two-thirds of the standard dose. In addition. it is necessary for liaison psychiatrists and other physicians to understand the interactions between psychotropics and drugs often used for treatment of renal diseases in order to prescribe psychotropics safely and effectively in renal patients.