In the upcoming 5G heterogeneous networks, leveraging multiple radio access technologies (RATs) shows to be a crucial issue in achieving RAT multiplexing gain to meet the explosive traffic demand. For always best connection (ABC), users tend to activate parallel transmission across all available RATs. However from a system-wide perspective, this might not be optimal given the context of network load, interference and diverse service requirements. To intelligently determine how to use these multi-RAT access resources concurrently, this paper proposes a joint multi-RAT user association and resource allocation strategy with triple decision and integrated context awareness of users and net-works. A dynamic game based ant colony al-gorithm (GACA) is designed to simultaneous-ly maximize the system utility and the faess of resource allocation. Simulation results show that it’s more reasonable to make multi-RAT association decision from a system-wide view-point than from an individual one. Compared to max-SNR based and ABC based strategies, the proposed method alleviates network con-gestion and optimizes resource allocation. It obtains 39%~70% performance improvement.