In Peru, companies within the textile sector encounter problems such as a decrease in the contribution to an industrial gross domestic product from 10.6 to 7.5%, a decline in financial credits by about 0.7% p.a., and the direct competition of Central American countries across the textile chain. The finishing of fabrics shows the worst performance, with losses of a 38.8% variation in industrial production and a 7.5% growth rate per textile industrial sector. In this scenario, a strategic lean procurement model based on 5S and supplier approval was designed. The lean objective is to streamline workflow in the raw material warehouse that generates excessive lead time to production and leads to unplanned downtime. In addition, supplier approval boosts procurement efficiency and provides strategic value in assessing and planning raw materials to ensure efficient supply. The model is validated through a case study involving a textile small and medium-sized enterprise (SME), and drastic improvements are made. These improvements address the problem of unplanned downtime by reducing its incidence and making economic contributions to the company.