The spinnability of semi-dilute poly(m-phenylene isophalamide) (PMIA) spinning dope was regulated by a small amount of surfactants to make it suitable for dry-jet wet spinning. OP-10 shows the best effect of lowering the surface tension of PMIA spinning dope among the selected surfactants. The effects of different amounts of OP-10 on surface tension and rheological behavior of PMIA spinning dope were investigated. Results show that when the content of OP-10 reaches 0.5 wt.%, the surface tension of the PMIA dope reduces to a minimum. The apparent viscosity of the PMIA dope increases with the increment of OP-10 contents. The dynamic viscoelasticity study shows that OP-10 also enhances the elasticity of the PMIA spinning dope. The spinning dope with 0.5 wt.% OP-10 can be smoothly spun by dry-jet wet spinning, and the obtained PMIA filament shows excellent mechanical performance.