A band-pass filter using spoof surface plasmon polaritons (SSPPs) and half-mode substrate integrated waveguide (HMSIW) for Ka-band RADAR application is proposed. In order to achieve the band-pass response, an HMSIW structure with high pass response and SSPPs with band-stop response are combined. Moreover, to investigate effects of geometric dimensions on the frequency characteristics of the proposed band-pass filter are examined by parametric analysis. It has been observed that lower cut-off and upper frequencies can be individually controlled just by changing the structural parameters. High Frequency Structure Simulator (HFSS) software was utilized to simulate the proposed structure. HFSS is the simulation tool for complex 3-D geometries and uses the finite element method (FEM). To validate the functionality, the proposed band-pass filter is fabricated on the dielectric material RT duroid 5880 with the dielectric constant εr = 2.2, height h = 0.508 mm, and dissipation factor tanδ = 4 × 10-4. The measured result shows return loss better than -10 dB and insertion loss less than 1.25 dB with the 3 dB fractional bandwidth (FBW) of 44.02% at the center frequency of 7.95 GHz.