An IRBFN (incremental radial basis function network) based Q-learning (IRBFN-QL) algorithm is proposed to upgrade the behavioural intelligence of robots. The key is to learn and store Q-value function based on adaptive growth of the structure and online learning of the parameters, to make robots learn the behavioral strategy autonomously and incrementally in unknown environment. Firstly, approximate linear independence (ALD) criterion is used to online increase the network nodes, thus the memory capacity of robots can grow adaptively along with the expansion of state space. The new added nodes change the inner connection of network topology. Kernel recursive least square (KRLS) algorithm is used to update the connection of network topology and its parameters, therefore the robot can extend and optimize its behavioral strategy constantly. Besides, L2 regularization term is integrated to KRLS algorithm to avoid the overfitting problem, which forms the L2 constrained KRLS (L2KRLS) algorithm. The experimental results show that IRBFN-QL algorithm can realize autonomous interaction between the robot and the unknown environment and gradually improve the navigation behavior ability of mobile robot in corridor environments.