This paper proposes a feasibility study of using Magnetic field property in detecting defects on printed circuit board (PCB) conductors. Simple microstrip transmission lines have been proposed and modeled as a non-defective line and defective lines in Computer Simulation Technology (CST) Microwave Studio in the purpose to observe the characteristic of magnetic field intensity (H) at 3 mm above the conduction lines. Types of defects that have been brought to study are stuck-at-faults and stuck-open fault. CST simulation has shown that the non-defective line induces a typically constant H field along the conduction line; however the defective lines produce high standing waves of H field at the points of defect. These results provide a very crucial knowledge in using magnetic field to diagnose and locate the defect detection on PCB. © 2012 IEEE.