The present paper describes the design and development of a series fed 1 ?? 12 resonant slotted array antenna at 38 GHz. Slot dimensions, their spacing and positions have been calculated for broadside radiation pattern. Gain of 16 dBi with VSWR 1.5:1 and side lobe level better than 10 dB has been achieved. The designed antenna is a part of a planer antenna of 65 ?? 12 slotted Array. The designed antenna has been simulated on ANSOFT HFSS EM simulator. The measured results are in excellent agreement with the simulated values.