Background <p>Longitudinal association of triglyceride glucose-Chinese visceral adiposity index (TyG-CVAI) with the risk of new-onset sarcopenia in middle-aged and older adults with diabetes remains unclear. This study aimed to investigate whether baseline and cumulative TyG-CVAI is associated with incident sarcopenia risk in middle-aged and older adults with diabetes.</p> Methods <p>We included participants aged ≥ 50 years with diabetes from the China Health and Retirement Longitudinal Study (CHARLS) 2011–2012. TyG-CVAI was calculated as TyG index multiplied by CVAI. Multivariable Cox regression and logistic regression were used to examine the associations of baseline and cumulative TyG-CVAI with new-onset sarcopenia. Receiver operating characteristic (ROC) curves were employed to compare the predictive capability of TyG-CVAI with its individual components.</p> Results <p>A total of 763 participants with diabetes were included in the baseline analysis. During the 4-year follow-up, 62 (8.1%) participants developed new-onset sarcopenia. Compared with the lowest quartile (Q1) of baseline TyG-CVAI, the highest quartile (Q4) was significantly associated with an increased risk of sarcopenia (HR = 2.368, 95% CI: 1.014–5.532) in the fully adjusted model, with a significant trend across quartiles (P for trend = 0.017). Compared with the low-stable group (Cluster 1, <i>n</i> = 198), the high-stable group (Cluster 2, <i>n</i> = 276) had a significantly higher risk of new-onset sarcopenia (OR = 1.100, 95% CI: 1.020–1.321). The predictive performance of baseline TyG-CVAI (AUC = 0.685, 95% CI: 0.611–0.747) and cumulative TyG-CVAI (AUC = 0.917, 95% CI: 0.845–0.962) was higher than that of baseline and cumulative TyG and CVAI.</p> Conclusion <p>Elevated baseline and cumulative TyG-CVAI are associated with new-onset sarcopenia in middle-aged and older Chinese adults with diabetes.</p>