A semiconductor device includes a semiconductor element, a base body, a conductive adhesive member, and a sealing member. The semiconductor element includes a substrate, a semiconductor element structure provided on the substrate, and p-electrode and n-electrode provided on the semiconductor element structure. The semiconductor element is disposed on the base body. The conductive adhesive member electrically connects the p-electrode and the n-electrode to the base body. The sealing member is provided to cover the semiconductor element on an upper surface of the base body. The conductive adhesive member contains particles selected from a group of (i) surface-treated particles having a particle diameter of 1 nm or more and 100 μm or less and (ii) particles that coexist with a dispersing agent.