To provide a synthetic fiber disperser for papermaking, providing excellent dispersion stability of fiber to provide a high-quality nonwoven fabric when producing the nonwoven fabric by papermaking method.

The disperser for the papermaking of a hydrophobic fiber comprises (A) a fatty acid monoester of an adduct of ethylene oxide and propylene oxide represented by general formula (1): R1COO-(C2H4O)m(C3H6O)n(C2H4O)p-H [wherein, R1 is a 15-21C fatty acid residue; m and p are each independently an integer of 3-35; and n is an integer of 25-45], and (B) an anionic surfactant regulated so that the ratio of the component (A) to the component (B) by mass is (40/60)-(90/10).