In order to explore the role of afforestation technology in responding to climate change, abnormal weather conditions such as snow melting need to be considered alongside evaluating the benefits of forest carbon sink ecological engineering afforestation technology. This paper adopts forest carbon sink ecological engineering afforestation technology based on a genetic fuzzy algorithm and combines static and dynamic economic evaluation indicators to evaluate the benefits. Dividing a wasteland in S City into regions and conducting group experiments, detailed measurements of indicators such as forest carbon storage, vegetation coverage, species richness index, and soil water retention capacity were carried out. The results showed that the experimental group’s forest carbon storage, vegetation coverage, and species richness were higher than those of the control group. The economic benefit evaluation indicators such as net present value (NPV), net present value rate (NPVR), internal rate of return (IRR), and benefit-cost ratio (BCR) were also better, proving the effectiveness of afforestation technology in improving forest carbon sink capacity and economic benefits.