This study aimed to explore the role of essential leadership styles of school principals in encouraging teachers' participation in professional learning communities (PLCs) in basic education schools in northeastern Thailand. It aimed to identify the nine leadership styles practiced by school principals and teachers' participation in PLCs, and to examine the relationship between them, utilizing a quantitative survey design with a questionnaire instrument that was returned by 731 respondents out of 750 distributed. Descriptive statistics were used to examine the perceived level of all variables and inferential statistics, applying Pearson's correlation coefficient and multiple regression to examine the relationships between the variables. The findings indicate that school principals are highly involved in practicing the nine leadership styles and teachers were also greatly participating in PLCs. Teachers' participation in PLCs was significantly related to the nine leadership styles at significance level of 0.05. The results also show that there were four significant predictors, namely learning, transformational, collaborative, and invitational leadership, which together contributed 55.6% of the variance in teachers' participation in PLCs. These findings contribute significantly to knowledge by proposing essential leadership styles that guide school principals in promoting teachers' participation in PLCs, which in turn will improve students' learning.