This research focuses on developing a magnetically supported catalyst for efficient transesterification reaction of used cooking oil (UCO). The catalyst consists of calcium oxide (CaO) and ZSM-5 zeolite, which were synthesized using waste chicken eggshell and rice husk. Meanwhile, magnetite (Fe3O4) was used as a magnetic component. Various magnetic zeolite-supported CaO catalysts (CaZ/Fe) were prepared with different amounts of CaO (10, 30, 50, and 80 wt% of zeolite) and Fe3O4 (1:0.5, 1:1, 1:1.5 and 1:2 of CaO-zeolite:Fe3O4 ratio). The results identified the 50CaZ/0.5Fe catalyst as the most effective. The catalyst displayed a high surface area, strong basicity, and ideal morphology, thus contributing to a higher biodiesel yield of 91%. The recovery rate of the 50CaZ/0.5Fe catalyst was 88%, suggesting minimal loss and easy catalyst separation post-reaction using an external magnetic field. It also displayed superior stability, obtaining 85% biodiesel yield after 4 uses. The activation energy calculated in the kinetic study was 14.085 kJ/mol. Moreover, the properties of the synthesized biodiesel met the standards set by the ASTM D6751. Overall, the 50CaZ/0.5Fe catalyst with good magnetic behaviour and exhibits excellent catalytic activity suggested that this catalyst is promising for application in biodiesel production.