The invention discloses a sulfur recovery and tail gas treatment system and a technology for comprehensive hydrogen production. The sulfur recovery and tail gas treatment system mainly comprises an SO2 generator, a two-stage reducing gas generator, a residual heat boiler, an overheated section condenser, a two-stage condensation cooler, a three-stage process gas preheater, a two-stage catalytic reactor, a hydrogenation reactor, a quenching tower, an absorption tower, a rich liquor pump, a rich and poor amine liquor heat exchanger, a regeneration tower, a calcination tower and the like. The sulfur recovery and tail gas treatment system and technology has the positive effects that the hydrogen source of hydrogenated sulfide is generated from the interior of facilities, thus avoiding an external hydrogen source adopted by an SCOT (Support Coated Open Tubular Column) technology; the function-compound two-stage reducing generator is especially arranged, so as to ensure a great amount of hydrogen needed for completely reducing sulfide; the reducing gas generator is arranged in a sulfur recovery region and not in a non-hydrogenation reaction region, thus being capable of better ensuring that the temperature needed in hydrogenation reaction is not overhigh, and the more thorough hydrogenation reaction can be guaranteed.