Aim of Study: This work aims to determine serum and synovial ‎levels of the granulocyte colony stimulating factor (G-CSF) in ‎order to evaluate their utility as biomarkers of disease activity ‎and severity in rheumatoid arthritis (RA) patients. Methods: ‎Thirty patients with established RA and a control group of 20 ‎apparently healthy individuals matched for age and sex to our ‎patients were included and thoroughly examined. Disease ‎activity was assessed using the modified disease activity score of ‎‎28 joint count (DAS28) while, disease severity was evaluated ‎using the clinical spread severity Index (SSI). Plain radiography ‎was done for all affected joints with evaluation according to ‎Laresn scores Serum and synovial levels of (G-CSF) were ‎measured by the ELISA technique.Conclusion: . Our results ‎reveal a critical role for G-CSF in driving joint inflammation and ‎highlight G-CSF as a potential therapeutic target in rheumatoid ‎arthritis.‎