Title: Solving Partial Label Learning Problem with Multi-Agent Reinforcement Learning. Abstract: Partial label learning (PLL) deals with classifications when a set of candidate labels instead of the true one is given for each training instance. As a weakly supervised learning problem, the main target of PLL is to discover latent relationships within training samples, and utilize such information to disambiguate noisy labels. Many existing methods choose nearest neighbors of each partially-labeled instance in an unsupervised way such that the obtained instance similarities can be empirically non-optimal and unrelated to the downstream classification task. To address this issue, we propose a novel multi-agent reinforcement learning (MARL) framework which models the connection between each pair of training samples as a reinforcement learning (RL) agent. We use attention-based graph neural network (GNN) to learn the instance similarity, and adaptively refine it using a deterministic policy gradient approach until some pre-defined scoring function is optimized. Different from those two-stage and alternative optimization algorithms whose training procedures are not end-to-end, our RL-based approach directly optimizes the objective function and estimates the instance similarities more precisely. The experimental results show that our method outperforms state-of-the-art competitors with a higher classification accuracy in both synthetic and real examples. 