本研究旨在探討企業投資決策對盈餘資訊性之影響,以及企業的穩健程度對投資強度-盈餘資訊性之影響效果。投資決策分別以研發支出強度與資本支出強度以及兩者加總來衡量;並以盈餘反應係數(ERC)與未來盈餘反應係數(FERC)來捕捉企業投資決策的盈餘資訊性;會計穩健性則採用Khan and Watts (2009) 延伸Basu (1997) 模型所發展的衡量指標(C_Score)。 實證結果發現,企業的總投資決策具有正向盈餘資訊性,而相較於研發投資決策,投資人對於資本投資決策給予較強的正向顯著盈餘資訊性。接著加入中介變數-會計穩健性後,發現穩健性較高之企業,研發支出決策具有當期盈餘資訊性;資本支出決策具有未來盈餘資訊性。綜言之,穩健性較高之企業,投資決策對盈餘資訊性具有正向顯著關係。 本研究提供有關企業投資決策對盈餘資訊性的影響,以及會計穩健性能提高企業投資決策與盈餘資訊性之間正向顯著關係的相關證據,本研究可供未來學者及投資人作為參考之依據。 ;The purpose of this paper is to investigate the impact of corporate investment decision on earnings informativeness, and the moderating role of accounting conservatism on the relationships between corporate investment and earnings informativeness. We separately use R&D, capital expenditure, the sum of R&D and capital expenditure to measure corporate investment. We also use earnings response coefficient (ERC) and future earnings response coefficient (FERC) to measure earnings informativeness. As for accounting conservatism, we use a measurement named C_Score, which Khan and Watts (2009) developed on the basis of Basu (1997)’s model. The empirical results indicate that corporate investment is significantly and positively related to earnings informativeness. Compared with R&D expenditure, investors have stronger positive response to capital investment decisions. After considering the moderating role of accounting conservatism, with higher accounting conservatism, corporates’ R&D expenditure is significantly and positively related to earnings response coefficient (ERC) ,while capital expenditure is significantly and positively related to future earnings response coefficient (FERC). Overall, corporate investment is significantly and positively related to earnings informativeness with higher accounting conservatism. This paper provides some evidences on the effect of investment on earnings informativeness, and moderating role of accounting conservatism can increase the effect between investment and earnings informativeness. This study can be used as reference for future scholars and investors.