Objective To explore mindful self-care level of oncology nurses and its influencing factors and to provide reference for constructing mindful self-care scheme to improve mental health of oncology nurses. Methods A total of 371 oncology nurses from 14 3A hospitals of Jinzhou, Shenyang and Dalian of Liaoning province were selected by convenience sampling.The general information questionnaire, Chinese version of Mental Health Literacy Scale, Perceived Social Support Scale, Self-compassion Scale and Chinese version of Brief Mindful Self-care Scale were used for survey.Multi-variate hierarchical regression analysis was used to explore the key factors affecting mindful self-care level of oncology nurses. Results The total score of mindful self-care of oncology nurses was (59.30±10.70) points;the total scores of mindful self-care and all dimension scores were positively correlated with the total scores of mental health literacy, perceived social support and self-compassion (P＜0.05 for all).After controlling the general information and mental health literacy, perceived social support and self-compassion were independent predictors of mindful self-care of oncology nurses, explaining 39.6% of total variance (P＜0.05 for all). Conclusion Oncology nurses′ mindful self-care level was at a low level, and nursing managers should take educational intervention according to the main influencing factors to further improve mindful self-care level of oncology nurses.