Lignocellulosic biomass can provide a consistent and sustainable source of bioenergy. Degraded empty fruit bunch (DEFB) from oil palm is a suitable candidate for biofuels and biochemicals production by using alkaline ethylene glycol pretreatment and two-staged acid hydrolysis. This paper provided several important physical and chemical properties of treated DEFB after alkaline ethylene glycol pretreatment. The dataset for analysis methods which were used in two-staged acid hydrolysis for the determination of reducing sugars, phenolic compounds, furfural and hydroxymethyfurfural (HMF) in the acid hydrolysate was also provided. The key information and dataset provided in this article can be useful for researchers to determine the product compositions from lignocellulosic biomass after the pretreatment and acid hydrolysis processes in the future.