Abstract Objectives To evaluate the association between toothbrushing behavior and cardiometabolic multimorbidity (CMM) among middle-aged and older adults. Methods Data from the Beijing Health Service Survey were used to estimate the association between toothbrushing behavior and the risk of CMM using multilevel logistic models (N = 18,158). Results There were 554 patients with CMM, with a prevalence of 3.05%. We found a higher risk of CMM for those with toothbrushing once or less (OR = 2.16, 95%CI: 1.80, 2.59) compared with those brushed two or more times per day in the crude model. After adjusting for confounding factors, the association between the two remained significant (OR = 1.68, 95%CI: 1.39, 2.04). The effect size was higher in adults with a higher education level (OR = 2.32) compared to those with a lower education level (OR = 1.39, P for interaction