Oxadiazole derivatives have potential uses as antidepressant, antibacterial, and antifungal agents. It has thus been a common research area to devise simple yet efficient ways to synthesize oxadiazole derivatives. Disubstituted 1,3,4-oxadiazoles have been synthesized from the reaction of 1-amino-2-phenyl-1,3,4-triazole with several aryl aldehydes, including 9-anthraldehyde, benzaldehyde, 3,5-dichlorosalicylaldehyde, and pyrrole-2-carboxaldehyde. This novel oxadiazole synthesis is straightforward and efficient, resulting in high yields of easily purified products. A rearrangement mechanism has also been proposed for the formation of 1,3,4-oxadiazoles through the above reaction. Evidence for the proposed mechanism includes the GC analysis of several products as well as an investigation of the importance of the aromatic ring within 1-amino-2-phenyl-1,3,4-traizole. We found that aryl aldehydes reacted with 1-amino-2-phenyl-1,3,4-triazole formed oxadiazoles, whereas the same aryl aldehydes reacted with 4-amino-1,2,4-triazole under identical conditions formed imines. It has thus been concluded that the aromatic ring on position 2 of the triazole is crucial for oxadiazole formation and that without this structural element, oxadiazole formation does not occur.