In the process of educating adolescents, good emotional development and life adjustment are two significant factors for teachers to know. This study employed random cluster sampling of senior secondary school students in Ondo and Oyo States in south-western Nigeria. The Random sampling was employed to select 1,070 students. The data collected were analyzed using means, standard deviation and factor analysis. Significant differences were found between students in Ondo and Oyo States concerning emotional intelligence (EI) and life adjustment (LA). Moreover, senior secondary school students in Ondo did not show significant differences in EI, according to several background variables, but their parenting style was associated with significant differences in terms of LA. Furthermore, of the background variables measured, only the factor of parents' marital status was not significantly different in terms of EI of senior secondary school students in Oyo. There was no significant difference in those students' EI according to birth order. A positive and modest correlation was found between EI scores of students in Ondo and Oyo. On the basis of the findings of this study, the researcher recommended that: educators in these schools implement a student consulting program to reinforce students' abilities of emotional control and to; provide gender education for mutual learning to help students learn how to deal with people. Moreover, teachers should integrate daily interaction with more diverse people in order to improve self-understanding. (Contains 3 tables and 1 figure.)