In crystals of chiral molecules, racemic crystals generally have a higher density and are thermodynamically more stable than crystals composed solely of optically active (enantiomeric) molecules (Wallach's rule). We consider that the mixing of enantiomeric pairs (i.e., racemization) drives molecular assembly and have examined its role in the construction of supramolecular structures. Conversely, mixing of opposite enantiomers results in the loss of optical activity. In this paper, we present a method for constructing thermodynamically stable and optically active supramolecular liquid crystals by mixing quasi-enantiomeric molecules in a 1:1 ratio (quasi-racemization). Quasi-enantiomers are defined as the molecules whose overall shapes are in a mirror-image relationship but some elements are different. Here we use octahedral metal complexes with D and L chirality as quasi-enantiomers and report the formation of thermodynamically stable supramolecular liquid crystals and the observation of unique chiroptical activity.