Abstract Nine sucrose octaesters of homogeneous fatty acid composition were prepared, and their physical properties were examined. From the melt the sucrose octaesters formed a stable phase having a diffraction pattern identical to that of the α-phase of trigly cerides. The evaporation of an acetone solution of a sucrose octaester gave a phase with a diffraction pattern typical of the β′-phase of triglycerides. No phase resembling the crystalline β-phase of triglycerides was produced from the melt or from solvent. The infrared spectra and the diffraction patterns of the sucrose octaester α-like phase are consistent with vertical alignment of the fatty acids, a hexagonal subcell of the methylene groups, and fatty acid chains extending from both sides of the disaccharide rings. The β′-like phase apparently differs from the α-like phase only in the intermethylene order indicated by the 0.377 nm spacing in the diffraction pattern of the β′-like phase. The viscosities of the sucrose octaesters were higher than those of triglycerides with the same fatty acid composition. High-melting triglycerides and sucrose octaesters showed limited miscibility with liquid sucrose octaesters.