Abstract: The innovative integration of industrial Internet and 5G is facing fundamental challenges of the deep convergence of operational technology (OT) and information and communication technology (ICT), resulting in the difficulty for wide-area 5G networks to meet field-level industrial control requirements. 5G LAN (local area network) overcomes the wide-area unicast networking model of standard 5G, and innovatively implements the local multicast networking model, making it a suitable solution for industrial wireless networks. We firstly make an in-depth analysis on the fundamental communication requirements of industrial wireless networks, such as high-concurrency access of heterogeneous tasks, deterministic wireless communication, and multi-protocol convergence, and provide a systematic review of the characteristics and evolution of 5G LAN technology. Then, we propose a 5G LAN-based industrial wireless network architecture supporting factory-level and enterprise-level networking. Furthermore, we propose the key technologies for 5G LAN-based industrial wireless networks, including virtual dynamic networking, ultra-reliable low-latency communications, hybrid forwarding at the data link and network layers, and broadcast/multicast communications. An experimental platform is established to conduct system-level testing. Finally, we discuss challenges and future research directions for 5G LAN industrial wireless networks in areas such as standalone deployment, edge intelligence enhancement, endogenous convergence of virtualized control, and network security.