Background: To explore the incidence of incision infections and dynamically monitor albumin (ALB) and C-reactive protein (CRP) levels after lumbar fusion.Methods: A total of 1,773 patients undergoing lumbar fusion in our hospital from March 2011 to March 2021 were selected and divided into the infection group and the non-infection group according to whether incision infections occurred postoperatively. The incidence of postoperative incision infections, the pathogenic characteristics and drug resistance of the pathogenic bacteria in patients in the infection group were analyzed. The general clinical data, serum ALB and CRP levels at different time points were compared between the two groups of patients, and the correlation between ALB and CRP levels was analyzed.ROC curve was used to evaluate the predictive value of serum ALB and CRP levels on the incidence of postoperative incision infections.Results: Of the 1,773 patients, 41 (2.31%) experienced postoperative incision infections. A total of 57 pathogens were detected, including 36 gram-negative bacteria (63.16%), 18 gram-positive bacteria (31.58%), and 3 fungi (5.26%). Among gram-negative bacteria, Pseudomonas aeruginosa had the highest resistance to ampicillin. Among gram-positive bacteria, Staphylococcus aureus had the highest resistance to penicillin and erythromycin. The age, BMI, the number of diabetes patients, levels of serum tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and procalcitonin (PCT) IL-8 at 1 d after operation in the infection group were significantly higher than those in the non-infection group (P<0.05). The serum ALB and CRP levels of the two groups differed over time, and the differences were statistically significant in terms of time, inter-group, time and inter-group interaction factors (P<0.05). Correlation analysis showed that ALB was significantly negatively correlated with CRP expression. Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) value of combined ALB and CRP detection was 0.856, which was significantly higher than that of single detection with ALB or CRP (P<0.05).Conclusions: Gram-negative bacterial infection was the main type of incision infection in patients after lumbar fusion. The changes in ALB and CRP levels were related to the incidence of postoperative incision infections.