Supramolecular gels have received a lot of attention due to their unique properties and potential applications. However, it is difficult to determine the relationship between the molecular structures of gelators and the influencing factors. To understand how the different alkyl chain isomers govern the gelation behaviors, benzene-1,3,5-tricarboxamide (BTA) derivatives have been designed and synthesized. Although these derivatives have the same molecular formula, the alkyl chain configurations are different on the amide bonds. The gelation behaviors indicated that BTA derivatives had obviously different gelation properties. Specifically, BTA–3C8 could only form organogels in cyclohexane, and it exhibited poor gelation properties. BTA–3MeC7 formed stable organogels in low-polar solvents. BTA–3EtC6 possessed excellent gelation properties, and it formed organogels in almost all the tested solvents. BTA–3BuC4 exhibited gelation abilities in a limited number of solvents. The thermal stabilities and the morphologies of organogels were determined. The results indicated that the alkyl chain groups of gelators significantly affected the thermal stabilities and the supramolecular structures of organogels. Using the FT–IR technique and XRD characterization, we investigated the main driving force and the molecular stacking patterns of the gelators. The results indicated that hydrogen bonds acted as the main driving force for the formation of gels. Moreover, the gelator molecules were self-assembled to form ordered and layered structures. Finally, the mechanism of the organogel formation was proposed. This study provides a useful idea for the preparation of soft materials with controllable supramolecular structures or special properties.