The light-emitting device of the present invention includes: a support; a plurality of light-emitting elements arranged in a row on the support; and a conductor trace portion configured from a plurality of conductor traces which extend on the support from one end portion of the row to the other end portion of the row which are each electrically connected to each of the plurality of light-emitting elements. Each of the plurality of conductor traces is configured such that the trace width in the direction of extension in a region under one light-emitting element to which the conductor trace is electrically connected is greater than the trace width in a region extending in the direction of extension side by side with a conductor trace connected to a light-emitting element disposed closer to the one end portion than the one light-emitting element is.