First to get the Android 4.1 upgrade will be owners of the HSPA+ version of Samsung's Galaxy Nexus, the same smartphone used to launch Android 4.0 Ice Cream Sandwich last autumn.
Unveiled at Google's I/O conference last month, Jelly Bean is claimed to provide a smoother, faster and more fluid experience compared to Ice Cream Sandwich.
The mobile OS includes a range of new features, such as offline voice typing, resizable widgets on the home screen and improvements to the camera and Android Beam.
It offers more sophisticated voice-based search results powered by the firm's Knowledge Graph - a mobile system viewed as Google's challenger to Apple's Siri system.
Jelly Bean users will also get access to Google Now, which scans their search history, calendar and location data to bring relevant information.
The system is designed to present information to users without them having to ask for it, such as weather forecasts when they wake up in the morning, or traffic information as they travel home from work.
"Google Now tells you today's weather before you start your day, how much traffic to expect before you leave for work, or your favourite team's score as they're playing," Google said in an update to the Nexus page on its Google+ social network.
Alongside Galaxy Nexus handsets, Jelly Bean will also roll out this month to Motorola Xoom devices following Google's recent multi-billion deal to acquire smartphone and tablet maker Motorola Mobility.
Reports suggest that Samsung's multi-million selling Galaxy S3 will get the operating system upgrade in the fourth quarter of this year, although nothing has been confirmed as yet on that.
Also this week, Google launched an iPad application for its social network Google+, which is claimed to have 250 million members worldwide.