In Korean hair, blue-dyeing causes severe hair damage due to a pre-bleaching step. Due to such damage, color retention period of the hair becomes very short. The prsent study aimed to address this problem, and to this end, samples were prepared as follows: blue-dyed hair (control group), dyed hair after pre-treatment with earthworms autolysate on bleached hair (pre-group), dyed hair with a mixture of dye and earthworms autolysate (mixed group). After blue-dyeing bleached hair once and 3 times, L*a*b* values measured to examine the color retention after shampoo application, at frequency once, 10 times, 20 times. For blue-dyeing, the hair was dyed well, where a* was close to ‘0’ in proportion to b* as brightness (L*) and yellow (b*) were relatively low. L*a*b* values were found to be highest in a pre-group when bleached hair (once, 3 times) was blue-dyed and shampooed up to 20 times while the color retention was the best in the pre- and mixed-groups. In regard to the dependence of color retention on shampoo frequency, the pre-group was more than 3 times greater than the control group and mixed-group. In terms of ‘dyeing uniformity’, ‘vividness’, ‘glossiness’ and ‘smoothness’, the pre-treated group was the best for both one-time and 3-times bleached hair. With respect to ‘texture roughness’, the control group was the highest. Regarding ‘hair dye deodorization effects’, the mixed group was the greatest. Just like the spectrophotometer measurement, the pre-treated group was the best at an expert group questionnaire. Since the earthworms autolysate treatment was found to enhance hair coloration and color durability during blue hair dyeing, it is reasonable to say that such treatment is commercially valuable.