The increase of older workers has resulted in more diversified demographics with a wide spectrum of employees' ages. This change calls for a better understanding of intergenerational conflict, in particular ageism. This study aimed to synthesize study findings on workplace ageism by examining the relationship between ageist attitudes and chronological age. A systematic literature review was conducted in accordance with PRISMA; then, 15 studies were included. The results of an intercept-only meta-regression model, using robust variance estimation with a random-effects approach, showed that an increase in workers' age had a significant negative association with the severity of their workplace-based ageist attitudes: b = −.159   (95% CI: −.21, −.11). Thus, the younger the workers, the more severe their ageist attitudes toward others in different age groups in the workplace. The findings offer implications for occupational social work practice in terms of priority in anti-ageism education and training among different age groups.