After a dominant, although not inspiring, performance, Liverpool got the goal which proved to be the winner through Daniel Agger's 43rd minute header.
However, Suarez, the striker upon whom Liverpool have become dependent, was cautioned in the second half for a foolish deliberate handball.
The yellow card was the Uruguayan's fifth of the season and he will therefore serve a one-match ban in his club's next game against West Ham United.
Liverpool's victory, which came in the wake of the midweek defeat at Tottenham, was only their third at home this season and they made it back-to-back league wins at Anfield for the first time since September 2011.
But in truth it should have been far more comfortable than it actually was, which is a familiar story where Liverpool have been concerned.
They had 14 shots in a totally one-sided first half, although Southampton could easily have had a goal of their own with Rickie Lambert's long-range shooting threatening to catch out Jose Reina.
The restoration of Lucas Leiva to the Liverpool side as defensive midfield linchpin after a three-month absence with a thigh injury transformed the dynamic almost immediately.
However, it took a double-dose of Uruguayan intervention to eventually help break the deadlock two minutes before the break.
Saints' South American summer signing Gaston Ramirez flattened international team-mate Suarez on the edge of the penalty area and, although the Reds striker crashed his free-kick onto the crossbar it rebounded to Johnson, whose cross was met by Agger's scoring header.
Southampton, having undertaken damage limitation in the first half, came out positively after the break and Liverpool struggled to reassert their dominance.
Such was Liverpool's desperation to score the second and give themselves some breathing space, Suarez instinctively tried to punch in Gerrard's fast-moving cross.
It proved costly as his subsequent booking ruled the side's leading scorer out of next Sunday's trip to West Ham, who beat Chelsea earlier on Saturday.