This study was carried out to investigate the effects of making an origami crane on the improvement of hand dexterity. Subjects composed of 20 normal adult males were randomly assigned to experimental and control groups of 10 people respectively. For the experimental group, a training of making an origami crane was conducted for 40 to 50 minutes a day during a 4-week training period. The control group was made to engage in everyday activities as usual. For pre and post assessment, Groove Pegboard test, Purdue Pegboard Test, and Jebsen Hand Function Test were used. The results on the effects of making an origami crane showed that there was a statistically significant difference in both the Grooved Pegboard test and Purdue Pegboard test(p<.05). In the Jebsen hand function Test, a significant difference was found in handwriting and building pieces of chess(p<.05), but there was no statistically significant difference in comparison with the right hand during the average performance of picking up small stuffs. The activity of making an origami crane for normal adults was confirmed to be helpful to improve the hand dexterity. Accordingly, making an origami crane is suggested to be an effective way to improve the hand dexterity.