A design of substrate integrated waveguide (SIW) based conical conformal slot array antenna is presented for X-band applications. The proposed design consists of two SIW arrays of 1 × 6 slot radiators located at ϕ = 0° and ϕ = 180°. The slotted arrays are fed using a rectangular waveguide (RWG) to SIW 1 × 2 T-junction power divider. The arrays are projected in the longitudinal direction on a conical surface having a lower and upper radius of 1.66λ
0 and 1.33λ
0, respectively. The power divider and SIW arrays are designed and simulated in full-wave EM simulation software. It is observed from the results that the proposed array has two main beams in the H-plane located at θ =
±
${\pm}$
90°, and have sidelobe levels (SLLs) of −23 dB and −20 dB, respectively. For the validation of simulation results, the proposed array is fabricated and measured, and a reasonable agreement is observed between both results.