關係人交易普遍存在於我國企業中，且具有相當的重要程度。根據文獻，關係人交易可能會對公司資訊品質造成負面效果。文獻亦指出分析師為公司與投資者間之專業資訊中介者，且係根據企業所發布財務報告之會計資訊作為盈餘預測的重要資訊來源之一，本研究探討關係人交易金額的多寡對分析師盈餘預測特性(準確性與離散程度)之影響，並進一步將關係人交易之雙方分為受相同會計師查核與受不同會計師查核時，對分析師盈餘預測特性之影響。 實證結果指出，當關係人交易金額愈大，分析師盈餘預測愈不準確且離散程度愈大。然而若關係人交易之雙方由相同會計師查核，可以減緩因關係人交易使分析師盈餘預測不準確與離散程度加大之影響。在台灣關係人交易盛行之環境下，關係人交易雙方之會計師選任效果可提供公司治理單位與投資人做為參考。 Related party transactions are prevalent and quite important to stakeholders in many countries including Taiwan. Prior studies find that related party transactions impair firms’ information quality. Literature also documents that analysts play a crucial role as an information intermediary between firms and investors, and they use accounting statements as one information source to make forecasts. The purpose of this research is to examine the effects of firms’ related party transactions on two analyst forecast characteristics, i.e., earnings forecast accuracy and dispersion. We also examine if those effects can be alleviated by same auditors auditing both sides of related party transactions. Our results show that related party transactions have detrimental effects on analyst earnings forecasts. We find that the amounts of related party transactions are negatively related with forecast accuracy and positively related with forecast dispersion. We also find that those effects are mitigated if both sides of related party transactions are audited by the same auditor. While related party transactions are considered as risk factors for material misstatement, our results can provide insights for firms, investors and regulators.