OBJECTIVE. To evaluate a novel light patch formulated for blue light delivery and topical activation of γ-aminolevulinic acid (ALA) during photodynamic therapy for the treatment of actinic keratosis (AK). MATERIALS AND METHODS. Ten volunteers with past unsuccessful treatment of AK were enrolled. Areas with AK lesions were treated with 20% ALA (Levulan) for an incubation period of 1 hour. Half of the area was treated with blue light patches (the patch emits 431 to 515 nm wavelength, 55.6 mJ/cm2 over 20 minutes), and the other half was left uncovered (control). The percentage of visible AK lesions cleared at the 3-month follow-up determined therapeutic efficacy. RESULTS. The mean lesion count for all treatment areas was decreased from 7.60 to 2.40 (p < .01). The subjects had slight burning or itching and mild to moderate erythema. One subject developed a blister at the treatment site. Controls had clearance of 30%, 17%, and 20% for the face, scalp, and hands, respectively. Patients were satisfied with the results and noticed an improvement in skin texture. CONCLUSION. Preliminary results show that the blue light patch is a potentially safe, effective, and alternative method for light delivery and topical ALA activation during photodynamic therapy of AK.