Abstract Objective: Phosphorylated Eukaryotic translation initiation factor 4E (p-eIF4E) is a critical regulator of protein synthesis and is phosphorylated by MNK1/2 to promote the translation of a mRNA subset. We have shown that blocking the eIF4E phosphorylation increased the anti-tumor immune response, especially the CD8 T cell activation. However, the role of p-eIF4E in CD4 T cell subsets, and in particular regulatory T cells (Tregs) is still unknown. The aim of this study was to explore the impact that the absence of p-eIF4E could have on the Treg activity as well as in an inflammatory context. Methods: To investigate the role of p-eIF4E on Tregs activity, we used genetically modified mice expressing a non-phosphorylatable form of eIF4E (KI mice). First, we analyzed Treg activity in WT and KI mice and the same mice subjected to dextran sulfate sodium (DSS)-induced colitis. We also analyzed the colonic immune cell infiltration using spectral flow cytometry and CODEX technology. Results: Using our mouse models, we observed that the p-eIF4E lack led to a decrease in Treg stability as well as a decrease in their ability to control the helper T cell (Th) proliferation. In the colitis context, we observed an increase in the disease severity in KI compared to WT mice characterized by an increase in colonic immune infiltration. Moreover, our mesenteric lymph node and colon immunophenotyping revealed a significant decrease in Treg, and an increase in Th expressing IFNγ in KI compared to WT mice. Finally, we observed a decrease in KI Treg ability to migrate to the lymph nodes. Conclusion: These results demonstrate for the first time the preponderant role of p-eIF4E in the control of Treg stability and Treg migration but also in their ability to regulate inflammation.