Keratosis lichenoides chronica is rare chronic dermatosis characterized by progressive development of licheniod papulonodules especially on the extremities and trunk. A 15-year-old male patient had erythematous to violaceous scaly patches and plaques on the left side of trunk and lower extremity along Blaschko's lines. Clinical and histologic findings were compatible with keratosis lichenoides chronica showing unilateral distribution.