Forced convection is sometimes employed in the cooling of electronic equipment operating at high heat dissipation rates. The heated electronic components are usually arranged evenly on the vertical circuit boards. To analyze the heat transfer of such electronic equipment, the forced convective heat transfer between two vertical parallel electronic circuit boards (ECBs) was investigated. The local heat transfer coefficient from the board was affected by the Reynolds number, the distance between the boards, and the distance from the channel entrance. Two empirical equations for calculating local Nusselt numbers for the heat transfer in a channel between vertical electronic boards were obtained. One was for an ECB surface with components, another was for its rear surface without components, and the range of Reynolds numbers was from 1500 to 9000.