Question: who does the voice of stewie family guy?
Answer: Seth MacFarlane

Seth MacFarlane voices three of the show 's main characters : Peter Griffin , Brian Griffin , and Stewie Griffin . MacFarlane chose to voice these characters himself , believing it would be easier to portray the voices he had already envisioned than for someone else to attempt it . MacFarlane drew inspiration for the voice of Peter from a security guard he overheard talking while attending the Rhode Island School of Design . Stewie 's voice was based on the voice of English actor Rex Harrison , especially his performance in the 1964 musical drama film My Fair Lady . MacFarlane uses his own voice while portraying Brian .