A circuit board structure includes a body, multiple first pads, a conductive assembly, multiple first engaging components, and multiple second engaging components. The body includes a first portion and a second portion integrally formed. A first surface of the first portion directly contacts a second surface of the second portion. A first region of the first surface protrudes from the second portion, and a second region of the second surface protrudes from the first portion. The first pads and the first engaging components are disposed on the first portion of the body and located in the first region of the first surface. The conductive assembly and the second engaging components are disposed on the second portion of the body and located in the second region of the second portion. The first pads are located between the first engaging components, and the conductive assembly is located between the second engaging components.