Purpose: This study scrutinises the correlation between earnings quality and agency cost based on corruption level and cultural values in six South-East Asian (SEA) countries: Indonesia, Malaysia, Philippines, Singapore, Thailand, and Vietnam.Design/methodology: We restrict categorisation of each SEA country whether they have low or high agency cost. This study employs 581 firm-years observations from the 30 biggest market capitalisation firms of six SEA countries. We run multiple regressions of three main accrual models for main analysis (Jones, 1991; Dechow et al., 1995; Kasznik, 1999) to get discretionary accruals.(#br)Findings: Results show that firms in low agency cost countries have lower earnings quality, and indicate that earnings management behaviour in this study is efficient... rather than detrimental. Furthermore, results present that firms with bigger size engage less in earnings management conduct compared to their counterparts.(#br)Originality/value: This study provides broader acknowledgement of how cultural values and corruption and their assumed correlation to agency cost could affect earnings management behaviour in South East Asia. We use a single proxy of high/low agency cost based on national cultural and corruption index.