The invention relates to the field of stope roadway hermetic retaining walls and particularly discloses a mould bag type rapidly-formed hermetic retaining wall which comprises a rectangular mould bag and filling slurry in the mould bag. The filling slurry can be rapidly formed after being filled in the mould bag, soft tie bars are arranged in the mould bag, and structures of reinforcement holes and the like are reserved in the mould bag to guarantee strength of the retaining wall. The retaining wall is safe, reliable, high in strength, good in hermetic effect, high in adaptability, simple in construction operation, rapid in forming and high in stability, rapid linkup of mining and filling is facilitated, and time consumption, intensity and cost in labor operation are greatly reduced.