The development of sustainable drop-in aviation fuels from non-edible, waste-based feedstocks is crucial for decarbonising the aviation industry. In this study, the catalytic deoxygenation of black soldier fly (BSF) larvae-, sardine waste-, and squid waste-derived oils was investigated using calcined dolomite–nickel oxide (DO–NiO) catalyst to produce renewable and sustainable biojet fuels. The fatty acid analysis revealed that lauric acid (28.06 %), palmitic acid (20.19 %), and myristic acid (16.00 %) were the predominant constituents of the BSF larvae oil, while high volumes of behenic acid (C22:0, 26.67 %) and arachidic acid (C20:0, 38.12 %) were present in the sardine waste oil. Crude oil analysis showed that the BSF larvae, sardine waste, and squid waste oils had a kinematic viscosity of 35.693, 28.889, and 27.768 mm2/s, respectively, and an acid value of 9.97, 32.58, and 16.32 mg KOH/g, respectively. The iodine values indicated that the oils were suitable as a feedstock for the production of biojet fuels. Upgrading of the oils with DO–NiO catalyst significantly enhanced the quality of the fuels, which led to the high-quality waste-derived biojet fuels with high flash points (up to 41 °C), and acidity below 0.1 mg KOH/g, which fulfilled the specifications defined by the ASTM D1655 standard. Upon blending with 10 % of Jet A-1 commercial aviation fuel, the density, kinematic viscosity, and calorific values of the resulting biojet fuel blends (BSFAV10, SAOAV10, SQAV10) were close to those specified for synthetic sustainable aviation fuels. These findings underscore the viability of waste oil valorisation via low-cost DO–NiO catalysis for the production of drop-in renewable biojet fuels, which aligned with circular economy principles and aviation sustainability goals. © 2025 The Author(s).