This disclosure discloses a method of manufacturing a light-emitting device includes steps of providing a first substrate with a plurality of first light-emitting elements and adhesive units arranged thereon, providing a second substrate with a first group of second light-emitting elements and a second group of second light-emitting elements arranged thereon, and connecting the a second group of second light-emitting elements and the adhesive units. The first light-emitting elements and the first group of second light-emitting elements are partially or wholly overlapped with each other during connecting the second group of second light-emitting elements and the adhesive units.