Industrial IoT (IIoT) is considered as the key technology for boosting Industry 4.0 revolution. However, the introduction of IoT devices and services raises new challenges in terms of cybersecurity. In this paper, a phase-based trust management framework for service-oriented IIoT (SOPHT) is proposed. This trust management (TM) model considers two trust levels at both plant and inter-plant. Plant TM enables the trustworthiness of IIoT plant nodes to be assessed dynamically and diversely in each phase, namely access control, service provider selection, service evaluation, and node classification. Inter-plant TM examines the trust between plants based on a three-phase mechanism. This trust management framework has been simulated under various attacks. The numerical results show its effectiveness and feasibility for safely evaluating the trust score of IIoT services at both plant and inter-plant levels, contributing thus to increasing the plant security and reliability.