Objective: Evidence shows that the host’s immune system interacts with tumor development and may be responsible for delaying tumor growth or even for its progression. Chronic inflammation has been identified as a key factor in the pathogenesis of ovarian cancer. The objective of this study is to carry out a comprehensive review of immunological aspects of ovarian cancer. Mechanism: A search of the following keywords was conducted in the PubMed database: “ovarian cancer”, “prognostic factors”, “immunotherapy”, “immune system”. The articles identified were published between 1992 and 2021. Findings in brief: A total of 75 articles were selected for further examination. Conclusions: The understanding of tumor immune escape mechanisms will improve immunotherapy treatments. This will allow personalization or treatment not only in accordance with the biology of the tumor, but also with the characteristics of the tumor microenvironment, expanding the benefit of immunotherapy and providing more effective responses.