The rocket was launched at 10:50 p.m. local time on Thursday (01:50 GMT on Friday).
The rocket is set to bring the satellite into the Sun-synchronous Low Earth orbit.
Vega is a small-lift launch vehicle named after the brightest star in the constellation of Lyra. The rocket was first launched in 2012.
The satellite's name PRISMA is short for "Precursore Iperspettrale della Missione Applicativa," it will be operated by Italy's national space agency.