Hobbs joined the station in July 2011 to host a new primetime show on Saturday nights, and began hosting relaunched early evening show Music: Response in September of the same year.
She wrote on her official Facebook page: "I've resigned from Xfm and I'm leaving on Thursday November 1st. I'd like to say thank you with all my heart to everyone who has spent some time listening to the shows. Incidentally, we have just recorded our highest listening figures ever, which I'm thrilled about.
"We've had an incredible year. Music: Response was nominated twice, for Best Specialist Show, at the radio industry's most prestigious Awards, the Sonys and Arqivas.
"But the most exciting element for me has been the opportunity to champion artists as gifted as Ben Howard, Jake Bugg [and] Lianne La Havas, many of whom have had Top 10 success with their debut records and are changing people's lives. I'd like to thank all of the artists who have contributed wonderful music, live sessions and interviews to Music: Response."
Hobbs continued by saying that she had "always wanted to prove" that "the electronic music that I love so much" could succeed in a Saturday evening primetime slow on radio, thanking "all the genius next generation producers who lit up the show".
She also paid tribute to her assistant Sam Davies, who was hired off the back of a work experience placement, describing him as "a superb asset to Xfm".
Hobbs's final show - a best-of programme featuring highlights from the past year and an appearance from special guest George Ezra - airs this evening (November 1).