Conventional direct coupled filters suffer from higher order mode passband in its stopband. This paper presents a novel technique to suppress the TE102 mode passband of direct coupled substrate integrated waveguide (SIW) bandpass filter. The suppression technique is based on the weak coupling between resonator/resonator and resonator/feed. This can be achieved by properly aligning the resonators as per the field of the resonator modes. A direct coupled band pass Chebyshev SIW filter of second order with a centre frequency of 20.8 GHz, fractional bandwidth of 0.02, and ripple factor of 0.01 dB is designed with the technique. The simulation result shows the passband at 20.8 GHz due to TE101 mode. The undesirable passband in the stopband of the filter due to higher order mode TE102 at 32.2 GHz is suppressed effectively. The maximum insertion loss achieved in the stopband of the proposed filter is −41 dB. The filter also generates a transmission zero above the passband at 23.1 GHz which improves selectivity. This shows the proposed technique can be used to suppress the undesirable mode passband in the direct coupled filter.