a daytime running light apparatus for a vehicle may include a lamp disposed in a daytime running light for a vehicle , configured to receive information about a vehicle starting condition , and determine whether to turn on the daytime running light , and a controller coupled to the lamp to control an amount of light of the daytime running light in accordance with illumination intensity or brightness at a periphery of the vehicle , in which the controller may be adapted to increase the amount of light of the daytime running light in proportion to an increase in illumination intensity or brightness at the periphery of the vehicle .