本研究檢測審計品質與經理人能力對於分析師盈餘預測行為之相對有用性。根據Compustat 及 I/B/E/S所蒐集之1996至2011年資料，本研究發現，相對於非四大會計師事務所或非產業專家，當公司被四大會計師事務所或產業專家查核時，分析師預測之準確度較高，且離散度較小。此外，本研究發現當公司經理人能力較高時，分析師預測之準確度亦愈高，而離散度亦愈小。最後，為探討沙賓法案對分析師預測行為之影響，本研究將樣本區分為沙賓法案前及沙賓法案後兩組。實證結果顯示，相對於沙賓法案前，在沙賓法案後，分析師較重視審計品質與經理人能力。整體而言，審計品質與經理人能力皆會為分析師的盈餘預測帶來正面影響，而經理人能力之影響較為顯著。 / This study examines the relative usefulness of audit quality and managerial ability on financial analysts’ earnings forecast behavior. Based on data collected from Compustat and I/B/E/S from 1996 to 2011, the empirical results show that analysts' earnings forecast accuracy is higher and dispersion is smaller when firms are audited by a Big 4 auditor or an industry specialist. Similarly, analysts' earnings forecast accuracy is also higher and dispersion is also smaller when firms employ more capable managers. To investigate whether SOX affects analysts’ behavior, sample is divided into pre-SOX and post-SOX groups. The regression results from both groups show that analysts take audit quality and managerial ability into their earnings forecasts after SOX. Overall, the results suggest that both audit quality and managerial ability are associated with analysts’ earnings forecast properties. Importantly, the effect of managerial ability appears to be larger than the effect of audit quality.