The Blaugrana unveiled a proposal to expand the capacity of their famous ground to 105,000 seats back in December, in a move that would include a retractable roof and increase matchday revenue by an estimated 29 million euros.
The initial plans were rejected by a local university which objected to a new stadium being built on its land. As a result any new structure will now be erected on the exisiting site rather than on a new plot.
Barca hosts Real Betis on Saturday evening and members have been invited to register their vote in a poll outside the ground during the day.
More than 50 percent of the club's 'socios' are expected to vote as the club looks to the build for the future on the back of a week which saw the Catalans banned from signing players for at least the next two transfer windows.
If approved, building work is scheduled to begin in 2017 and conclude by 2021.