This study aimed to assess the elfect of potassium ferrate (PF) on the co-fementation system of waste activated sludge (WAS) and corn straw (CS) under alkaline conditions. Laboratory-seale sequencing batch reactors were used to investigate the impact of various PF dosages (0, 0.05, 0.20, 0.50 g/g VSS_WAS) on the enhanced solubilization, hydrolysis, and the formation of short-chain fatty acids (SCFAs) in the co-fermentation system. The results showed that PF pretreatment enhanced the dissolution of organic matter in both WAS and CS. After a 24-hour pretreatment, the levels of soluble chemical oxygen demand (SCOD), soluble polysaccharides, and prteins in the 0.50 g/g VSS_WAS PF dosage group increased by 11.9, 9.41, and 4.75 times compared to the non-dosage group, respectively. The makimum accumulation of SCFAs at various PF dosages (0, 0.05, 0.20, 0.50 g/g VSS_WAS) increased by 1.47, 1.92, and 2.21 times, respectively, compared to the non-dosage group, and the proportion of acetic acid, which is easily utilized by microorganisms, also increased. Microbial community analysis revealed a decrease in the Shannon index and an increase in the abundance of Firmicutes and Bacteroidota in the experimental groups. Acid-producing fermentative bacteria such as Macellibacteroides, Bacteroides, Rikenellaceae, and Clostridium were predominant in the system. Clostridium, an iron-reducing bacterium, could be selectively enriched at high concentrations of Fe(Ⅲ) , further enhancing its abundance. The fermentation supematant with PF had higher SCFA content and lower phosphorus (P) content, making it suitable as a carbon source supplement for wastewater treatment plants. Additionally, the formation of vivianite was observed in the experimental groups, facilitating P recovery. When PF was added at 0.20 g/g VSS_WAS, the recovery potential of SCFAs and P was good, and the economic benelit was the highest, reaching 63.96 CNY/m^3 WAS. Therefore, the recommended PF dosage was 0.20 g/g VSS_WAS, providing a reference for the resource utilization of WAS and CS.