Bis(monoacylglycero)phosphate (BMP) reveals an unusual sn-1,sn-1‘ stereoconfiguration of glycerophosphate. We synthesized sn-(3-myristoyl-2-hydroxy)glycerol-1-phospho-sn-1‘-(3‘-myristoyl-2‘-hydroxy)glycerol (1,1‘-DMBMP) and characterized the thermotropic phase behavior and membrane structure, in comparison with those of the corresponding sn-3:sn-1‘ stereoisomer (3,1‘-DMBMP), by means of differential scanning calorimetry (DSC), small- and wide-angle X-ray scattering (SAXS and WAXS, respectively), pressure−area (π−A) isotherms, epifluorescence microscopy of monolayers, and molecular dynamics (MD) simulations. In DSC, these lipids exhibited weakly energetic broad peaks with an onset temperature of 9 °C for 1,1‘-DMBMP and 18 °C for 3,1‘-DMBMP. In addition, a highly cooperative, strongly energetic transition peak was observed at ∼40 °C for 1,1‘-DMBMP and ∼42 °C for 3,1‘-DMBMP. These results are supported by the observation that 1,1‘-DMBMP exhibited a larger phase transition pressure (π_c) than 3,1‘-DMBMP. Small- and wide-angle X-ray scattering measurements identified these small and large energetic transitions as a quasi-crystalline (L_c1)−quasi-crystalline with different tilt angle (L_c2) phase transition and an L_c2−L_α main phase transition, respectively. X-ray measurements also revealed that these DMBMPs undergo an unbinding at the main phase transition temperature. The MD simulations estimated stronger hydrogen bonding formation in the 3,1‘-DMBMP membrane than in 1,1‘-DMBMP, supporting the experimental data.