As a novel technology of IMT-2020 network and beyond, network slicing allows the creation of multiple virtual networks on top of a shared physical infrastructure and meets diverse needs of users and applications. Meanwhile, Artificial Intelligence (AI) makes it intelligent especially by empowering network slice management and orchestration. This Recommendation aims to evaluate the intelligence level for network slice management and orchestration in IMT-2020 network and beyond and mainly covers the following aspects: overview, intelligence level definition, evaluation methods, framework and procedures of intelligent network slice management and orchestration.