This paper systematically examines the impact of green credit regulation on the efficiency of corporate green investment. The results show that green credit policy significantly decreases green investment efficiency for heavily polluting firms. This is further evidenced through the fact that these firms are more inclined to make symbolic efforts to pursue more credit resources rather than engaging in substantive green investments to drive real green transition. This negative effect is more pronounced for small, non-state-owned and non-foreign-funded firms. Our further analysis suggests that the intensity of environmental law enforcement, the level of financial development, and intellectual property protection can mitigate this negative effect of green credit policy on green investment efficiency. Our study is groundbreaking in that it makes the first attempt to calculate the future value that green investment can create, which serves the basis for analyzing the economic effects of green investment at the industry level. The findings indicate that labor-intensive industries with close ties to consumers' daily lives have a higher future value for green investment. Conversely, capital-intensive industries such as the metallurgical industry have a lower future value for green investment. These findings emphasize the need to improve green credit regulation and make genuine green investment to accelerate real green transition in emerging economies.