Franklin array antennas are considered as one of the most competitive candidates for millimeter-wave (mmW) 5G applications due to their compact size, simple geometry and high gain. This paper describes a microstrip Franklin antenna array for fifth generation (5G) wireless applications. The proposed modified Franklin array is based on a collinear array structure with the objective of achieving broad bandwidth, high directivity, and dual-band operation at 22.7 and 34.9 GHz. The designed antenna consists of a 3 × 3 array patch element as the radiating part and a 3 × 3 slotted ground plane operating at a multiband resonance in the mmW range. The dimensions of the patch antennas are designed based on λ/2 of the second resonant frequency. The designed antenna shows dual band operation with a total impedance bandwidth ranging from 21.5 to 24.3 GHz (fractional bandwidth of 12.2%) at the first band and from 33.9 to 36 GHz (fractional bandwidth of 6%) at the second band in simulation. In measurement, the impedance bandwidth ranges from 21.5 to 24.5 GHz (fractional bandwidth of 13%) at the first band and from 34.3 to 36.2 GHz (fractional bandwidth of 5.3%) at the second band, respectively. The performance of the antenna is analyzed by parametric analysis by modifying various parameters of the antenna. All the necessary simulations are carried out using HFSS v.14.0.