Purpose: To determine the efficacy of an 810-nm diode laser in the treatment of trichiasis. Methods: Noncomparative interventional prospective study of 87 patients, providing 153 eyelids with darkly pigmented trichiatic eyelashes, treated with the 810-nm diode laser. The number of trichiatic eyelashes was counted before and after treatment. Patients were followed for 6 months with monthly examinations. Results. Immediately after laser treatment, the average number of trichiatic eyelashes per patient was reduced from 3.50 (standard deviation, 4.20) to 0.40 (standard deviation, 1.0). Forty-one patients were followed for 3 or more months (minimum of 90 days; maximum, 443 days; standard deviation, 77.23 days). Among these patients, the average number of eyelashes per patient was reduced from 3.58 (standard deviation, 4.15) to 0.73 (standard deviation, 1.60). The paired t tests demonstrated a statistically significant difference between numbers of eyelashes before and after laser treatment irrespective of gender, age, or location of eyelashes. Conclusions: The 810-nm diode laser is an effective tool in treating trichiasis.