The invention discloses a nonwoven-fabric-container seedling culture bag using zippers to regulate size. The nonwoven-fabric-container seedling culture bag is characterized in that first connecting parts are arranged on the upper portion, the lateral side and the bottom of a nonwoven fabric bag body, second connecting parts are arranged on the lower portion and the lateral side of a deepened nonwoven-fabric supplement part, the second connecting parts are connected with the first connecting part on the upper portion of the nonwoven-fabric bag body, a widened nonwoven-fabric supplement part comprises a nonwoven-fabric bottom edge, a nonwoven-fabric lateral edge and third connecting parts, the nonwoven-fabric bottom edge is connected with the nonwoven-fabric lateral edge, the third connecting parts are arranged at the edges of the nonwoven-fabric bottom edge and the nonwoven-fabric lateral edge, and the third connecting parts are connected with the first connecting parts on the lateral side and at the bottom of the nonwoven-fabric bag body. By the arrangement, the nonwoven-fabric-container seedling culture bag has the advantages that the problem that the size of an existing nonwoven-fabric seedling culture bag on the market is fixed when the seedling culture bag leaves a factory is solved, the space of the seedling culture bag can be increased according to plant growth conditions, seedling culture bag waste can be prevented, plant root system damage can be prevented, and seedling culture quality is guaranteed.