Purpose This study aimed to analyze the current status of rapid weight-loss based on sex and to examine the physical and mental challenges faced by elite adolescent taekwondo athletes who competed in both domestic and international events in 2023. Methods The Rapid Weight-Loss Questionnaire was used as the survey tool. Taekwondo athletes completed the questionnaire twice within a week after the official competition, and the average values were used as data. The T-test was employed to determine the weight-loss period and weight loss of Taekwondo athletes based on sex. Additionally, the chi-square test was conducted to ascertain whether there were differences in weight-loss methods and physical and mental changes. The level of statistical significance was set at P<.05, and data processing was carried out using SPSS version 27. Results The average weight-loss period for Taekwondo athletes was 8.85 ± 3.73 days, with an average weight loss of 3.60 ± 0.62 kg. The weight-loss period and weight-loss amount were similar for male and female athletes. Both sexes used dehydration and food intake restrictions, to achieve weight loss. The physical and mental challenges experienced during weight loss, including lack of energy, dizziness, muscle spasms, irritation, and decreased concentration, were similar for male and female athletes. Both male and female athletes obtained information about weight loss mainly from colleagues, coaches, and the Internet. Conclusion Elite adolescent taekwondo athletes engage in rapid weight-loss, leading to similar physical and mental distress across the sexes. Therefore, a safe and systematic weight loss method is necessary.