The deployment of heterogeneous networks (Het-Nets) is a promising candidate for the next-generation wireless networks. This is envisioned to deliver higher rate data services in flexible and cost-effective manner. However, in the HetNets, due to the coexistence of various nodes, traffic load variations are more pronounced which requires more dynamic resource management. On the other side, the effective management of resource can significantly impact on the experience of user equipment (UE) and network's performance. In this paper, we address a joint UE association (UEA) and downlink resource allocation problem in the HetNets. In this regard, we propose a UEA policy based on base stations' (BSs') estimated load and signal-tointerferenceand-noise-ratio at the location of UE. Furthermore, we apply a self-organizing mechanism to allocate the resource for jointly optimizing the power and channel allocation in a fully distributed way. Our proposed joint UEA and self-organizing resource allocation balances load among BSs and improves the energy efficiency of the network. Simulation results show that our proposed joint UEA and resource allocation yields significant performance gains up to 26.4% and 22% compared to the other benchmark schemes in terms of average energy consumption and average BS load, respectively.