In this paper, the reflection loss of a slotted triangular patch antenna is studied. The slotted triangular patch shows lower reflection loss compared to a conventional triangular patch antenna. Emphasize is given to lower the reflection loss at the broadside modes. Using this method, the potential of using a slotted triangular patch as a multiband patch antenna is further enhanced. Reduced reflection loss can be obtained not only at the broadside modes' resonant frequencies but also other higher order resonant frequencies. This is achieved by placing triangular slots nearby the magnetic field nulls. The patch antennas are simulated using HP High Frequency Structure Simulator (HFSS). © 2006 IEEE.