Copper aluminate is a p-type semiconductor material with moderate thermoelectric behavior. In contrast, for the first-time electron-enriched cobalt was introduced as a dopant to accelerate the thermoelectric performance of the spinel CuAl2O4. The spinel phase was confirmed by XRD analysis, and the band agreed with Cu–O–Al bond at 790 cm−1 from FT-IR spectra. SEM and TEM analysis established the morphology of cubic CuAl2O4 and spherical cobalt. Depending on the dopant concentration, the Co2+ ion successfully resided in the position of Cu2+ in the spinel CuAl2O4. From the Tauc plot, a bandgap reduction from 2.1 eV to 1.01 eV was detected, which is accountable for outstanding enhancement in the thermoelectric behavior of the material. We have effectively fabricated the flexible undoped and cobalt-doped Copper aluminate, Cu1-xCoxAl2O4 (x = 0, 0.02, 0.04, 0.06, and 0.08) on the fabric substrate. 8 % (x = 0.08) cobalt doped over copper aluminate were designated the more charge carriers of −6.84 × 1016 cm−3, promoting high electrical conductivity to reach a maximum of 1.02 Scm−1. In particular, the power factor of 114.92 μWm−1K−2 was achieved for Cu0.92Co0.08Al2O4 at 300 K. Our results thus indicate that the cobalt-doped CuAl2O4-coated fabrics are promising semiconducting candidates for flexible wearable thermoelectric applications. The maximum output voltage of 2.4 mV was achieved for the fabricated p-type CuAl2O4 and n-type Cu0.94Co0.06Al2O4 thermoelectric device at ΔT = 2.7 K.