The present invention provides a solution bag that is used for medical treatment and stores solution used for an apparatus for analyzing blood chemistry that measures and analyzes the concentrations of electrolytes, the partial pressures of gases, and the concentrations of metabolites or the volume ratio of red blood cells contained in blood. The solution bag for an apparatus for analyzing blood chemistry of the present invention includes: a receptacle that contains a solution; a valve body that is attached to the receptacle and has a through-hole longitudinally formed therein; a valve spool that is disposed in the through-hole of the valve body; and a solution leakage preventing unit that is disposed in the valve spool, in which the valve body has a flow channel and a solution discharging pipe spaced at a predetermined distance from each other.