A compact and novel multi band series fed array antenna is simulated and analyzed for antenna applications in millimeter-wave frequency ranges. The single element antenna performance is investigated for different flexible substrate materials like Rogers Ultralam, Arlon Diclad 880, Neltec NY9220, Taconic TLY, Polyethylene and Polystyrene in initial stages. The proposed series fed array antenna operates (S11<-10dB) in 14.7-20.8GHz, 23.125.8GHz, 28.5-34.8GHz and 39.3-44.8GHz frequency bands. The designed antenna exhibits negative group delay characteristics from 18.2-19.9GHz, 29.9-33.3GHz, 39.4-42GHz and 42.6-43.6GHz. It achieved a peak gain of 13.9dB at 42.5GHz and radiation efficiency of 97.5% at 33GHz. Results obtained are in fine conformity and therefore, proposed antenna is preferable for mmwave applications.