In current study, the synthesis and characterization of novel thermally stable polyimides (PIs) containing an 1,3,4-oxadiazole moiety based on a diamine, i.e. 2,5-bis(3-amino-4-methyl benzene)-1,3,4-oxadiazole (BAMO), have been reported. The polymers were characterized using FT-IR and elemental analysis (CHN). Thermal and mechanical behaviours of the prepared PIs were studied by thermo-gravimetric analysis/differential thermal analysis TGA/DTA, and dynamic mechanical thermal analysis (DMTA). The obtained results reveal PI (4), which was obtained from BAMO and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) exhibited the best thermal and mechanical properties.