Di(2-ethylhexyl) phthalate (DEHP) is a commonly used plasticizer known for its toxic effects on the male reproductive system. Green tea polyphenols (GTPs), recognized for their antioxidant and anti-inflammatory properties, have demonstrated protective effects on various organs, but the mechanisms by which GTPs mitigate DEHP-induced testicular damage remain unclear. Healthy male C57BL/6J mice were divided into five groups: control, DEHP, DEHP + GTP treatment, GTP, and oil groups. Testicular histopathological changes were assessed using hematoxylin-eosin (H&E), periodic acid-Schiff (PAS), and Masson staining. Ultrastructural alterations were examined through transmission electron microscopy. High-throughput sequencing was performed to analyze the expression of mRNA, miRNA, and lncRNA and construct an lncRNA-miRNA-mRNA regulatory network for identifying key regulatory axes. Mice in the DEHP group exhibited significant testicular damage, including reduced sperm count, mitochondrial deformation, and endoplasmic reticulum dilation. GTP treatment notably improved testicular structural integrity, restored sperm count, and alleviated mitochondrial and endoplasmic reticulum damage. Additionally, DEHP significantly increased activated CD8+ T cells, which were reduced with GTP treatment. High-throughput sequencing revealed that GTP treatment exerted protective effects through the regulation of six key lncRNA-miRNA-mRNA axes. GTPs significantly protect against DEHP-induced testicular damage, and the lncRNA-miRNA-mRNA regulatory axes play a potential role in this process.