The orthorhombic crystal packing of 15-trans-triacontene was determined from electron diffraction intensities observed from epitaxially oriented and from solution-grown samples and by infrared spectroscopy of melt-crystallized thin layers. As determined from systematic absences in Okl and hhl patterns, the pseudo-orthorhombic space group is Aa with cell constants a = 7.48(3), b = 4.99(3), and c/2 = 39.8(1) Angstrom. The structural conformation around the trans double bond is very similar to that found earlier for odd-chain polyalkenamers; i.e., the single bonds adjacent to the olefinic group have shew and anti-skew arrangements. Infrared spectra indicate that the formal molecular centrosymmetry around the double bond is not preserved by the chain conformation in the solid state. The chain layers stack in a way reminiscent of the B-polymorphic packing of odd-chain n-paraffins. In keeping with this chain jog, the olefin is completely insoluble in the solids containing the paraffin with the same carbon number, n-triacontane.