Abstract: Polypropylene(PP)tows for mid or high-speed filter rod maker was developed. The results indicated that strength of the PP tows was decreased by adding a new modifier and increase of spinning temperature, the density, stability, and openning-ability of the tow packed were increased significantly by selecting polypropylene polymers and spinning oil properly, substituting spinneret, and improving crimping device and packer. The PP tows could meet requirement of mid or high-speed filter rod maker and its machinability was close to that of acetate tows.