The study was developed in three stages to establish a strengths scale for adolescents in Taiwan. In the first stage, the participants were 438 junior high students and 73 junior high teachers and data related to the strengths of junior high students were collected; we created questions about the scale based on the results. In the second stage, after expert validation was conducted, we conducted a pretest on 170 junior high students and established a formal scale. In the third stage, we verified the reliability and validity of the scale. The participants were 431 junior high students, (218 boys (50.6%) and 213 girls (49.4%) between the ages of 12 and 16 years (M = 14.31, SD = 0.85). The strengths scale for adolescents in Taiwan contained 47 items and nine constructs, namely introspection and responsibility; creativity and curiosity; dream and ambition; activeness and humor; altruism and cooperativeness; happiness and gratitude; friendliness and amiability; reframing and relief; and optimism and hope. High scores indicate a high degree of strengths in a specific construct. The Cronbach’s α of each subscale was between .80 and .93, and the factor loadings of each subscale were between .486 and .952. The correlativity of each factor was between .39 and .70. The result of a confirmatory factor analysis showed a good fit; the component reliability was between .61 and .91. The average variance extracted of the subscale, optimism and hope, was .35, and that of the other subscales was between .47 and .71. The correlation between each latent factor ranged from .42 to .82. Overall, the results indicated good construct validity and criterion validity. The study reported that among the nine subscales, creativity and curiosity scored the highest, whereas activeness and humor scored the lowest. Gender differences were only noted in altruism and cooperativeness. Finally, the results and suggestions for application and future studies were discussed.