A semiconductor light-emitting device includes a light-emitting structure including a first semiconductor layer, an active layer and a second semiconductor layer sequentially stacked. A connection electrode is positioned above the light-emitting structure. The connection electrode includes a connection metal layer electrically connected to at least one of the first and second semiconductor layers. A UBM pattern is on the connection electrode. A connection terminal is on the UBM pattern. The connection metal layer includes a first metal element. A heat conductivity of the first metal element is higher than that of gold (Au). The connection terminal includes a second metal element. A first reactivity of the first metal element with the second metal element is lower than a second reactivity of gold (Au) with the second metal element.