In this study, the performance and exhaust emissions characteristics of gas turbine engine fuelled with blends of waste cooking oil biodiesel with Jet A-1 is investigated experimentally. The blending ratios define the percentage of biodiesel in the mixture and the used blend ratios were blend 10% (B10), blend 20% (B20) and blend 50% (B50) on volume bases. The biodiesel fuels were produced using transesterification process and characterized according to American Society for Testing and Materials (ASTM) biodiesel specifications. Chemical and physical properties show a good potential of using waste cooking oil biodiesel blends as an alternative for Jet A-1. The gas turbine engine performance parameters and exhaust emissions were measured over a range of throttle setting and compared with the measured parameters of the gas turbine engine when fuelled with 100% Jet A-1. The experimental results show that, the static thrust of the gas turbine engine was reduced when the engine operated with blends of waste cooking oil biodiesel compared to that of 100% Jet A-1. In addition, the engine rotational speed was reduced while operating the engine with waste cooking oil biodiesel blends. The thrust specific fuel consumption (TSFC) for biodiesel blends was higher than that for Jet A-1. On the other hand, the values of carbon monoxide (CO) and Nitrogen oxides (NOx) concentrations for biodiesel blends were lower compared to that of Jet A-1.