A steel sheet and a manufacturing method therefor are provided.A steel sheet has a component composition and contains 6 to 80% of ferrite and 20 to 94% of a microstructure composed of one or two or more of upper bainite, fresh martensite, tempered martensite, lower bainite, and retained γ, and contains 7 to 20% of retained γ, where: an area ratio (SγUB) of retained γ having a particle width of 0.18 to 0.60 μm, a particle length of 1.7 to 7.0 μm, and an aspect ratio of 5 to 15 is 0.2 to 5%; and a total area ratio (SγBlock) of fresh martensite having an equivalent circle diameter of 1.5 to 15 μm and an aspect ratio of 3 or less and/or retained γ particles having an equivalent circle diameter of 1.5 to 15 μm and an aspect ratio of 3 or less is 3% or less (including 0%).