Pair learning (PL) in robotics education is derived from pair programming, and impacted by many factors. Two important factors were identified including roles assignment and learning styles in this study. The roles assignment involved Driver-Navigator Pair and Software-Hardware Pair. For the learning style, the dimension of active/reflective was adopted. Therefore, a 2*3 factorial design was employed with the between-subjects factors roles assignment and learning styles. After a one-semester robotics course, we evaluated 66 fifth-grade students' learning achievements, attitude towards robotics, engagement, mental efforts, compatibility, and attitude towards PL. The results indicated that there was no statistically significant difference among different pairs in the above six indicators. Moreover, there was no significant difference in the learning outcomes among pairs of different learning styles. One important explanation is that the joint effect of PL might bridge the difference in learning performance that may be caused by learning style.