Abstract: The present invention provides an artificial cerebrospinal fluid containing 120 to 160 mEq/L of sodium ion, 1 to 6 mEq/L of potassium ion, 75 to 155 mEq/L of chloride ion, and 5 to 45 mEq/L of bicarbonate ion, and provides an artificial cerebrospinal fluid further containing at least one component selected from the group consisting of 10 g/L or less of a reducing sugar, 5 mmol/L or less of phosphoric acid, 5 mEq/L or less of calcium ion, and 5 mEq/L or less of magnesium ion. The artificial cerebrospinal fluid of the present invention can prevent or reduce the incidence of cerebral edema and can further suppress brain cell disorders when used as an irrigation fluid or perfusion fluid in the field of neurosurgery, such as intracranial surgery, or when used as a replenishing fluid for lost cerebrospinal fluid.