Changes of contents of reducing sugar and sucrose and activities of sucrose-phosphate synthase, sucrose synthease and invertase from the leaves of barley (Hordeum vulgare L. cv. Chalssal) seedlings grown at $4^{circ}C$ were investigated, and the property of acid invertase were also examined. In the seedlings grown at $4^{circ}C$ for 3 days, the contents of reducing sugar and sucrose were increased to 1.3 and 2.4 times, respectively. Activity of acid invertase was decreased markedly by cold treatment while the activities of sucrosephosphate synthase, sucrose synthase, and alkaline invertase were not changed. In acid phosphatase purified partially by ammonium sulfate fractionation and DEAE-Sephacel column chromatography, the $K_m$ value for sucrose was 9.5 mM and the optimum pH and temperature was 5.5 and $35^{circ}C$ respectively. This enzyme was supposed to be ${eta}-fructosidase$ by studies on the substrate specificity and the molecular weight was estimated to be 63 Kd by Sephadex G-200 gel chromatography.graphy.