Objective To study the role and effect of FEM1B in apoptosis of HIV reservoir ACH-2 cell lines. Methods A lentivirus used to overexpress FEM1B in ACH-2 cell lines. FITC-annexin-V/7-AAD staining was used to assess spontaneous cell apoptosis and cell apoptosis under TRAIL stimulation. Viral loads in culture supernatants were examined by qPCR. Results Spontaneous cell apoptosis remained unchanged in FEM1B-overexpressing cell lines. Cell apoptosis and viral loads in culture supernatants under TRAIL stimulation were significantly increased. Conclusions FEM1B increases TRAIL-mediated cell apoptosis and viral loads in culture supernatants of HIV reservoir cell lines.