A network signal coupling circuit installed in a circuit board and electrically coupled between a network-on-chip and a network connector is disclosed to include a coupling module installed each channel thereof, each coupling module including two capacitors respectively electrically connected in series to the two circuits of the respective channel, two sets of equivalent resistors respectively electrically connected in parallel to opposing ends of the capacitors, and two signal equivalent grounding terminals respectively electrically connected to the two sets of equivalent resistors; by means of the characteristic of the capacitors that the strength increases when the frequency rises, the signal coupling performance of the signal coupling circuit is relatively enhanced when the applied network frequency is increased.