Background: Poly-T repeat lengths of rs10524523 in TOMM40 together with APOE polymorphism have been reported to affect the risk of late-onset Alzheimer's disease (LOAD) and the age of onset (AOO). Objective: To explore whether the AOO and cerebrospinal fluid biomarkers Aβ42, total tau and phosphorylated tau are associated with different repeat lengths. Methods: We conducted both the fragment and sequencing analysis of rs10524523 in 336 LOAD patients with a known APOE genotype. Results: AOO and Aβ42 levels associated significantly with certain poly-T repeat lengths of rs10524523 in LOAD patients encompassing APOE 34/44 genotype. Conclusion: We conclude that the poly-T repeat associations of rs10524523 in TOMM40 reflect the APOE ε4-dependent association in LOAD.