Changes in the alcohol-soluble free amino acids during germination of a spring grain, Wanju and two winter grains, Sedohadaka and Nonsankwa No.1-6 which are differing in their degree of spring (winter) habits, were investigated by thin layer chromatography. The results obtained are as follows. 1. Throughout the germination period, 25 ninhydrin positive components; 22 amino acids including two amides and 3 unknown spots were detected. It is interesting to note that identification of histidine was confined to Wanju and Sedohadaka but Nonsankwa No.1-6, which has the lower degree of spring habit. 2. Except the quiescent seeds, the major components were generally composed of the acidic and neutral amino acids together with glutamine and asparagine. 3. Proline was contained in higher quantity except from the stage of quiescent seeds, but the outstanding difference among the varieties was not recognized. Whether this component is related to the mechanism of spring habit in barley or not is a problem to be studied more. 4. In all the varieties, most of the changes in amino acid levels during germination were usually in the same direction and of the same pattern under the temperature controlled not to be varnalized. In view of the results above, the changes in the amino acid levels seem to be more affected by the changes of growing circumstances and the subsequent metabolic activities of certain enzymes than by the characteristics of varieties themselves.