To evaluate axial length (AL) measurements and detection rates using a swept-source optical coherence tomography (SS-OCT) biometer (OA-2000, Tomey, Japan) compared with the IOLMaster (v5.4, Carl Zeiss Meditec AG, Germany), Lenstar (v2.1, Haag-Streit, Switzerland) and ultrasound (US) measurements in eyes with vitreous hemorrhage (VH).Eye Hospital of Wenzhou Medical University, Wenzhou, China.Comparative evaluation of a diagnostic test or technology.The main outcomes were AL measurement failure rate and agreement in AL measurements in patients with VH. The Bland-Altman method was used to assess the agreement between devices.In total, 40 eyes were scanned with each of the four biometers. For Forrester grade III, detection rate was 100%, 41.7% and 41.7% with OA-2000, IOLMaster and Lenstar respectively. For Forrester grade I and II, detection rate was 46.4%, 3.57% and 3.57% with OA-2000, IOLMaster and Lenstar respectively. The detection rate with US was 100% for all grades. Bland-Altman limits of agreement between the four biometers indicated excellent agreement: OA-2000 vs IOLMaster (95% LoA -0.15 to 0.05mm), OA-2000 vs Lenstar (-0.04 to 0.12mm), OA-2000 vs US (-0.3 to 0.56mm).In VH, the detection rate with the SS-OCT biometer OA-2000 was better than the IOLMaster and Lenstar. In cases were all biometers were able to acquire an AL measurement, excellent agreement was found.