The loss of engineered cells and the cytokine release syndrome represent two major drawbacks of Chimeric Antigen Receptor (CAR)-T cell therapy. The engineering of hematopoietic stem cells (HSCs), by providing a continuous replenishment of CAR-T cells, could circumvent these issues. To avoid a potentially dangerous pan-hematopoietic CAR expression, we designed a T-cell specific specific synthetic promoter to restrict the CAR expression only to T cell progeny issued from CAR-modified HSCs. Methods: Potential sequences for T-cell specific expression were designed in silico and cloned in GFP or CD22-CAR vectors. Specific expression was assessed in cell lines or primary peripheral blood cells. We then transduced CD34+ cell and humanized NSG mice or differentiated them on OP9-(DL4)-culture system. Results: Upon transfection with GFP under the control of our synthetic promoter, only Jurkat cell line (T cells) or primary T cells expressed GFP. When transduced HSCs were co-cultured with on OP9-DL4 cells or injected into NSG mice, the transgene was expressed only in T cell lineage. We also validated that CAR expression under our promoter was detectable and functional in in vitro cytotoxicity assays. Indeed, primary T cells transduced with CAR under our promoter showed the same lysis activity against leukemic cell lines as a classic strong promoter . Conclusion: Our results show that we could generate a new synthetic promoter with a lineage specificity. This new strategy could help overcome side effects while improving CAR-T cells persistence and could be used for both hematological malignancies and solid tumors after autologous transplantation.