The original project, which starred Shaun Evans as a young Endeavour Morse, attracted 8.2m viewers in January.
Evans will reprise the role in four 2-hour episodes, to be filmed in Oxford later in 2012. Also returning from the pilot are Roger Allam (Inspector Fred Thursday), James Bradshaw (Dr Max Debryn) and Abigail Thaw, daughter of original Inspector Morse star John Thaw.
"It was fantastic that the audience responded so warmly to Endeavour," said ITV drama's Sally Haynes. "Shaun's portrayal of a legendary character was captivating and Endeavour thoroughly deserves a series - there's so much more we can do with the character."
Producer Dan McCulloch added: "We're delighted to be making a series of Endeavour and have been overwhelmed by the reaction to the first film.
"Russell Lewis has some bold plans to further enrich the mythology of Morse, introducing some significant new characters, and re-establishing some old favourites, all of whom are destined to have a massive impact on the future inspector's life."
The new series will be produced by McCulloch and executive produced by Mammoth Screen's joint managing directors, Michele Buck and Damien Timmer.
Last year, Shaun Evans told Digital Spy that he was eager to reprise the role of Morse in a full series of Endeavour.
"I certainly had a good time and I feel like, in terms of the story and where he's at, there's definitely room for growth," he said.
In addition, a further four two-hour episodes of Inspector Morse spinoff Lewis will air on ITV1 from May.
Kevin Whately (Lewis) suggested earlier this year that the show would not last "a lot longer", adding that he is "now police retirement age".
Some are born great, some achieve greatness and some have greatness thrust upon them.
The rest of us are a bit crap.