This study examined product innovation and competitive advantage in selected plastic manufacturing industries in Onitsha. The precise goals of this study are to ascertain the contribution of sensing capability, seizing capability, and transformation capability to the achievement of competitive advantage. The dynamic capability theory underlies this investigation. The study used a descriptive research design for its study. Personnel from four specific Onitsha plastic factories make up the study's population of 168. Taro Yamane’s formula was employed to get a sample size of 120. The study's data were produced using a structured questionnaire. Primary data were collected from the respondent. The data gathered were analyzed using multiple regression method. The study found that sensing capability, seizing capability and transforming capability had significant positive relationship with competitive advantage. The study concludes that product innovation has significant positive relationship with competitive advantage in plastic manufacturing industries in Onitsha. The study made several recommendations, including that businesses constantly strive to invest in diverse new product ideas and improve the existing products in order to get a competitive advantage over rivals.