The fast-growing use of supramolecular hydrogelators as biomaterials for a variety of applications, ranging from wound healing to drug delivery to tissue engineering, has highlighted the importance of synthetic design over recent years. Here, we report a new class of nanosheet stereocomplexes in aqueous solution and at physiological conditions (i. e., pH7.4), which are formed by physically mixing right- and left-handed tripeptide supramolecular hydrogelators without any external stimulus. Such tripeptides were obtained by incorporating either α-aminoisobutyric acid (Aib, U) or alanine (Ala, A) at the C-terminus or middle position of known peptide hydrogelators containing naphthalene and two phenylalanine residues. For hydrogels of these peptides, our results show that their morphologies and physical properties changed upon mixing with the L- and D-forms of the peptides forming suspension stereocomplexes. These interactions reduced molecular mobility by forming new structures with new properties and, therefore, increased the thermal stability of the compound promising for numerous medical applications.