This paper investigates whether manager’s opportunistic earnings-increased real discretion negatively affects firm’s future operating performance. I analyze three types of earningsincreased real discretion, that is, sales manipulation through price discounts, reduction of discretionary expenses such as research and development expenses, and overproduction to report lower cost of goods sold. And, I try to specify opportunistic part from earnings-increased real discretion. Then, I take account of two circumstances. One is a low capability to increase accruals, and the other is a meeting or beating earnings benchmarks. I define opportunistic choice as earnings-increased real discretion with such circumstances. The results indicate that opportunistic real discretion has a significant negative influence on future operating performance （ROA）.