Cameroonian striker Samuel Eto'o made his long-awaited comeback after three months on the sidelines and came through unscathed.
Striker Cristian stunned the home crowd after three minutes when he unleashed a long-range drive that went into the top corner.
The poor positioning of Barca keeper Victor Valdes couldn't help him dive properly to block the swerving shot.
Brazilian playmaker Ronaldinho leveled the score four minutes before the interval, converting a penalty after Cristian brought down Andres Iniesta inside the area.
Spanish international Xavi gave the Catalans all three points in the 70th minute when he notched home on the rebound's after Carles Puyol's cross was poorly palmed by the keeper.
Barcelona are second in the league table with 31 points, four adrift of leaders Real Madrid. Struggling Deportivo lie second from bottom on just 13 points.