Background <p>Previous studies on the association between tooth loss and mortality typically relied on a single assessment of baseline tooth count. Therefore, we aimed to examine whether tooth loss progression was associated with mortality independently of baseline tooth count among older adults, using data from the Chinese Longitudinal Healthy Longevity Survey.</p> Methods <p>A total of 8073 older participants were included (median age: 83.0, interquartile range: 73.0–91.0; men: 46.6%). The exposure was tooth loss progression, which was assessed by annual tooth loss and categorized into four groups: stable (0 teeth/year), slow loss (&gt; 0, &lt; 2 teeth/year), moderate loss (≥ 2, &lt; 4 teeth/year), and rapid loss (≥ 4 teeth/year). The study outcome was all-cause mortality, with Cox regression analysis used to examine the association between tooth loss progression and mortality.</p> Results <p>During a median follow-up period of 3.5 years, a total of 5176 deaths (64.1%) were recorded. Overall, mortality risk significantly increased with a more rapid progression of tooth loss after adjusting for baseline tooth count and other confounding variables. Compared to the stable group, adjusted hazard ratios (HRs) for mortality were 1.11 (95% CI: 1.03–1.20) for the slow loss group, 1.20 (95% CI: 1.09–1.32) for the moderate loss group, and 1.33 (95% CI: 1.19–1.48) for the rapid loss group, respectively. Furthermore, in the restricted cubic spline models, a positive linear relationship was observed between annual tooth loss and mortality (adjusted HR: 1.04, 95% CI: 1.03–1.05, per one tooth loss).</p> Conclusions <p>Among older adults, the risk of all-cause mortality significantly increased with a more rapid progression of tooth loss, regardless of baseline tooth count. These findings emphasize the critical importance of monitoring tooth loss progression.</p>