This paper presents the propensities of preference for Human Robot Interaction (HRI) according to different personalities and facial expressions of humans and robots. This study is based on two types of personalities: extroverted and introverted. According to the personality, the facial expressions are distinguished to express extroversion and introversion. The design of experiment is a 3 (participant's group of personality: extrovert, intermediate, introvert) x 2 (robot's groups of personality) between-subjects experiment (N=40) in which participants interact with KMC-EXPR robots expressing either extroversion or introversion. The results showed an unprecedented hypothesis, unexpected implications and certain propensities of preferences.