Outsourcing logistics is one of the most substantial and strategic decisions in organizations. Organizations that wish to develop and improve their supply chain activities need a comprehensive, economical, and practical framework to assess and select logistics service providers (LSPs). The effectiveness of logistics services helps organizations to meet the expectations of customers. In this paper, a methodological framework comprising Grey Analytic Network Process and Grey Relational Analysis is proposed to evaluate and select preferred LSPs under uncertainty. To illustrate the capability of the proposed framework, the proposed framework is applied to assess LSPs in an Iranian automotive company.