In order to communicate securely in wireless sensor networks, secret keys between neighbor sensor nodes must be established. Until now, a number of key pre-distribution schemes have been proposed but these schemes have serious drawbacks of demanding memory overhead and having a weakness for node capture attack. Recently, practical key pre-distribution schemes using deployment knowledge are being proposed to improve these drawbacks. By using expected location information of sensor nodes a priori, memory overhead could be reduced and increase the resilience to node capture attack. However, in consideration of limited resource of sensor nodes, there should be an additional research at the same time. In this paper, we suggest an efficient random pair-wise keys scheme using expected location information a priori. Our analysis shows that our scheme improves the performance as well as the resilience of the networks compared to previous works. Moreover, our scheme ought to be able to add new nodes securely.