Early detection and treatment of maxillofacial space infection (MSI) can lead to successful outcomes; however, delayed intervention may result in severe systemic manifestations, posing a potential threat to life. The purpose of this study was to measure the association between albumin (ALB) levels and MSI severity. This was a retrospective cohort study including patients who were diagnosed with MSI at the Second Hospital of Lanzhou University from 2013 to 2023. Patients with unknown etiology, incomplete data, and those with psychiatric disorders and malignant tumors were excluded. Cured subjects are defined as the absence of clinical symptoms. The primary predictor variable was the ALB levels measured at the time of admission. We categorized ALB levels at admission into <30g/L, 30-35g/L, and >35g/L. The outcome variables were MSI severity measured by the length of stay (LOS) and death. LOS >14days was a prolonged length of hospital stay. Covariates included age, sex, involved anatomical spaces, neutrophil proportion and white blood cell counts. Statistical analysis was conducted using Pearson's χ2 test, one-way analysis of variance, independent sample t-test, multivariate logistic regression, Fisher's exact test, Kruskal-Wallis H test, Mann-Whitney U test, and the Gamma test. The P value was set at .05. This study encompassed 201 patients, of whom 123 were male (61.19%) and 78 were female (38.81%). Among these, 190 subjects (94.53%) were cured. The mean LOS was 16.38±18.93days, and 81 subjects (42.63%) had a LOS exceeding 14days. There were 11 deceased patients (5.47%). The neutrophil proportion (χ2=8.31; P<.01), and white blood cell count (χ2=11.14; P<.01) were significantly higher in deceased patients compared to those who were cured, and among the deceased patients, there was a greater percentage of patients with odontogenic infections (χ2=7.48; P=.02). There was no difference in ALB levels among the deceased patients (χ2=3.08 P=.21). A reduction in ALB levels is associated with an increased risk of prolonged LOS (χ2=21.77; P<.001). The relative risk (RR) of LOS extension when the ALB level is between 30 and 35g/L is 1.32 times higher than when the ALB level exceeds 35g/L (RR=1.32, 95% confidence interval (CI)=0.99 to 1.76). Furthermore, when ALB levels fall below 30g/L, the RR increases to 2.19 times higher compared to ALB levels greater than 35g/L (RR=2.19, 95% CI=1.47 to 3.26). Moreover, the LOS was used to measure the severity of MSI. Multivariate regression analysis found ALB levels were negatively associated with LOS. Subjects with ALB levels less than 30g/L had a 2.98 times higher risk (95% CI=1.12 to 7.75; P=.03) than subjects with ALB levels more than 35g/L. The risk factors of MSI including the ALB levels less than 35g/L (odds ratio (OR) (>35:30 to 35:<30)=1.00:1.85:2.98), multiple space infections (OR (1:2-3:4-5:>5)=1.00:0.52:1.92:5.49), and descending necrotizing mediastinitis (OR=4.30). ALB levels less than 35g/L, multiple space infections, descending necrotizing mediastinitis occurrence, and increased LOS are risk factors for increased severity of MSI and may lead to prolonged LOS.