The 19-year-old defender signed a long-term deal with the north London club on Monday after the FA Cup winners agreed a £16m fee with Southampton.
Chambers becomes Arsenal’s fourth signing of the summer after the arrivals of Barcelona forward Alexis Sanchez, Mathieu Debuchy and goalkeeper David Ospina.
The England Under-21 international follows in the footsteps of 20-year-old Oxlade-Chamberlain by swapping the south coast club for Arsenal.
Oxlade-Chamberain posted on Instagram: “New chambo in town… Okok! @chambers1995 welcome to Arsenal bro”
Earlier on Monday, Chambers spoke of his admiration for former Southampton stars Oxlade-Chamberlain and Theo Walcott.
“Massive [inspiration]. Even from a young age in the academy, everyone looked up to them and everyone wanted to do what they are doing,” Chambers told Arsenal’s website.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news