Background The average sleep quality of mariners during ocean voyages is notably worse than that of the general populace, and the incidence of sleep disorders among them is higher. Sleep disorders closely associate with fatigue and cognitive decline, increasing error and accident rates, and are a major safety hazard in marine navigation. At present, research on factors influencing the sleep quality of mariners during ocean voyages in China is limited and needs further investigation. Objective To investigate the sleep quality of mariners during ocean voyages and analyze its influencing factors, in order to provide reference for constructing sleep intervention plans and mitigating their sleep disorders. Methods Using convenience cluster sampling, a questionnaire survey was carried out in 408 crew members of a fleet who returned from a voyage on March 21, 2024. The questionnaires included a general information questionnaire, Pittsburgh Sleep Quality Index (PSQI) , and Self Rating Anxiety Scale (SAS), and the data were analyzed by SPSS 26.0 software. Results A total of 399 valid questionnaires were collected, with an effective recovery rate of 97.8%. The mean score of PSQI for the mariners during ocean voyages was (6.41±2.44), with 33.6% (134/399) of the mariners reporting sleep disorders. The PSQI scores varied by family structures (t=2.235, P=0.031), labor types (F=3.789, P=0.023), noise exposure (F=53.218, P＜0.001), dietary patterns (F=63.311, P＜0.001), exercise habits (F=16.416, P＜0.001), and anxiety states (t=5.963,P＜0.001). The results of linear regression showed that incomplete family structure (β=0.102, P=0.010), noise exposure (β=0.323, P<0.001), and anxiety (β=0.117, P=0.006) positively associated with the total score of PSQI, while dietary patterns (β=-0.331, P<0.001) and exercise habits (β=-0.147, P<0.001) negatively associated with the total PSQI score, and the 5 variables jointly explained 38.9% of the total variation in the PSQI score (F=37.159, P<0.01). Conclusion The sleep quality of mariners during ocean voyages is relatively low and the incidence of sleep disorders is relatively high, which is jointly influenced by factors such as family structure, noise exposure, dietary habits, exercise habits, and anxiety.