OBJECTIVE To evaluate the long-term endothelial cell loss after implantation of Worst-Fechner and Baikoff ZB5M anterior chamber intraocular lenses. METHODS Jiménez-Díaz Foundation and San Carlos University Hospital, Madrid, Spain. METHODS Preoperative and serial postoperative specular microscopy was performed on 30 eyes that had a Worst-Fechner lens and on 28 eyes that had a Baikoff ZB5M lens to correct high myopia. A video specular microscope adapted to an image analysis system was used to analyze the endothelium for cell density. Follow-up was 24 months. RESULTS In the Worst-Fechner lens group, postoperative endothelial cell density was significantly lower than preoperative density at all times (P < .001). Endothelial cell loss was 7.26% at 3 months, 10.64% at 6 months, 13.00% at 12 months, and 17.60% at 24 months. In the Baikoff ZB5M lens group, postoperative cell density was also significantly lower than preoperative density at all times (P < .001). It was 7.50% at 3 months, 10.94% at 6 months, 12.33% at 12 months, and 12.30% at 24 months. Cell loss did not stabilize between 1 and 2 years after surgery in the Worst-Fechner group (P = .047). However, no additional cell loss was noted during this period in the Baikoff ZB5M group (P = .968). Endothelial cell densities in the two groups did not differ during the first year. However, 2 years after surgery, cell density in the Worst-Fechner group was significantly lower than it was in the ZB5M group (P = .048). CONCLUSIONS Endothelial cell loss during the first year was similar in eyes with Worst-Fechner and Baikoff ZB5M lenses; however, at 2 years after surgery, endothelial cell loss was higher in eyes with Worst-Fechner lenses than it was in eyes with Baikoff ZB5M lenses.