In this study, polypropylene (PP) and carbon nanotube (CNT) were melt-compounded to prepare a CNT masterbatch, which was subsequently let down to targeted CNT loadings. PP/CNT multilayer composite films were fabricated via a blown film extrusion process. The effects of CNT content on film properties were systematically investigated by evaluating changes in mechanical performance and structure-related characteristics. In addition, the imbalance between machine direction (MD) and transverse direction (TD) properties, originating from processing-induced anisotropy, was quantified and addressed by controlling key extrusion parameters to reduce MD/TD deviation. The results provide practical insights into property enhancement and process stabilization of CNT-based functional multilayer films produced by scalable blown film manufacturing. This work was supported by KOITA grant funded by MSIT(KOITA20250002-18)