The present invention discloses a structure of a single-sided PCB within an ExpressCard with SMD LEDs arrangement formed thereon. The SMD LEDs are act as status indicators for the electronic devices with small, thin and compact size. The structure is expected to form SMD LED illuminating light to the top surface of the PCB with SMD LEDs connecting to the bonding pads on the bottom surface of the PCB. The method comprises forming through-holes on the PCB, placing SMD LEDs over the through-holes with their illuminating heads facing toward the top surface of the PCB, soldering the SMD LEDs with the bonding pads on the bottom surface of the PCB.