[Purpose] This study aims to empirically test whether the relationship between R&D expenditures and firm value depends on firm characteristics such as firm life cycle, technology level, and future growth prospects. Through this study, we also verify the effectiveness of R&D expenditures as an index of firm value evaluation.
 [Methodology] The research model is a modified version of the Ohlson model (1995), and 13,720 financial data of Korean listed firms extracted from KIS-VALUE and TS-2000 are used as samples. The technology level of the firms is classified by Eurostat Indicators, and the future growth prospects are classified according to the book-to-market ratio (BM ratio).
 [Findings] First, when analyzing all firms, we find that growth-stage R&D expenditures are more value-relevant than mature-stage R&D expenditures. However, when firms are divided into four groups (2×2) based on technology level and future growth prospects, we find that growth-stage R&D expenditures are more relevant to firm value than mature-stage R&D expenditures, only the group that satisfies at least one of the high-tech firms or firms with good future growth prospects. For non-high-tech firms and those with poor future growth prospects, there is no significant difference in the value relevance of growth-stage versus mature-stage R&D expenditures. Second, for all firms in the growth stage, we find that R&D expenditures have a greater impact on firm value than net income. Third, when dividing the growth stage firms into four groups (2×2) we find that R&D expenditures is more relevant to firm value than net income only for high-tech firms with good future growth prospects. In conclusion, R&D expenditures is a valid valuation indicator, and its relevance to firm value is higher for high-tech firms that are in the growth stage and have good future growth prospects.
 [Implications] R&D expenditures can be more effective valuation indicator when used in conjunction with the life-cycle stage, technology level, and future growth prospects (BM ratio) indicators. In addition, R&D expenditures can be useful in explaining the growth stock effect, in which high-tech firms in the growth stage or firms with good future growth prospects have market capitalizations that are higher than their underlying value.