A control chart for the water absorption of barley in the material treatment of shochu making walproposed. Water absorption tests were carried out by two methods: the custom method (CusM) using spontaneous draining, where the surface water on barley grains is absorbed naturally, and centrifugal separation method (CenM). The relations of water absorption to integrated temperature at steeping (TtA) in CusM and CenM (ZA+B and ZA) were obtained to be Z_A+B=5.41 Tt _A^0.28 in CusM, and ZA^0.40 in CenM. Under the same steeping condition, water absorption in CusM was approximately 10% higher than that in CenM. This result is due to the absorption of water from the water adherent on the surface of steeped barley grains. Intense expansion of barley grains was observed in CusM when resting time after steeping was long, and this process was controlled by the length of resting time irrespective of the water absorption rate. The realtionship between the integrated temperature of resting time ( Tt _s) and the water absorption rate (Z_A+B) was expressed as _TtB=13.43 Z_A+B^1.46.The control chart of steeping time and resting time in CusM was represented by using equations, Tt B=13.43 Z_A+B^1.46, and Tt A=0.0024 Z_A+B^3.57.