The refinery oily sludge poses a significant challenge due to its complex composition and adverse environmental impacts. Conventional remediation methods often involve high costs and generate secondary pollutants. This study investigates the bioremediation potential of using food waste digestate as renewable resources to improve the biodegradability of refinery oily sludge. The characteristic physicochemical properties of oily (OS) sludge and food waste digestate (FWD) on pH was 5.35 and 7.52, moisture content was 6.98% and 97.22%, total solid residue was 93% and 2%, ash content 1.51% and 0.25%. Then, MLSS and MLVSS for oily sludge and food waste digestate was 164,880 mg/L, 163398 mg/L, 8440 mg/L and 7748 mg/L. The identification of bacteria in food waste digestate by Gram staining method shows that bacteria as Gram-positive, specifically of the Bacillus species. Hydrocarbon degradation was studied using gravimetric analysis. The experiment shows that higher ratios of food waste digestate result in higher degradation with 23.94% on day 11. The effect of different ratios FWD and time incubator on seed germination over a period of 21 days shows that the control condition had 3 seeds germinated, the 1:1 ratio had 4 seeds, and the 1:3 ratio had 6 seeds germinated. The highest leaf height was observed in the 1:3 ratio that reached 24.8 cm, compared to 20.3 and 22.8 cm in the control group and 1:1 ratio.