Uytman will join in the New Year after a year-and-a-half at Emap's heavy rock station. Prior to that, he was at Beat 106 in Scotland for four years.
Nick Davidson, Xfm Network managing director, said: "Adam's knowledge, skills and programming ability, plus his haul of four Sony Gold awards this year, show this is a radio programmer at the top of his game. I'm delighted to welcome Adam to Xfm and GCap Media, and I'm confident that this begins our next stage of audience growth and critical and industry acclaim."
Ashton oversaw the development of the indie music station over the last five years, and helped to launch the second Xfm station in Manchester last year.
Xfm parent GCap Media said Ashton's departure was by mutual consent.
Ashton said: "I have had a fantastic time at Xfm over the last five years building one of the world's best radio brands. I have some amazing achievements and memories to look back on, and I look forward to watching Xfm go from strength to strength. The time is now right for me to embrace an exciting future."
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