Advanced Intelligent Customer Service System (AICSS) is a customer service system that integrates artificial intelligence (e.g., large language model, multimodal large model, NLP, ASR and TTS.) technology, omnichannel access, omni media interaction, and multimodal interaction capabilities. It aims to provide customers with reliable, efficient, unified customer service experiences, and improve the work efficiency of agents while reducing the customer service costs for enterprises. This Recommendation specifies the requirements and framework of the Advanced Intelligent Customer Service System (AICSS). Typical use cases of AICSS are provided in an appendix. This Recommendation can be used to guide relevant parties in the design, development, selection, and evaluation of the construction of the advanced intelligent customer service system.