Malignant ascites resistant to conventional drugs frequently affects ovarian cancer patients at the end of life. Here we report the case of a patient who benefited from complete resolution of ascites after low dose intraperitoneal administration of bevacizumab. Immunological analyses showed an initial increase in proportion and function of CD8(+) effector T cells and a reduction of circulating T(reg) cells. A review of the current literature regarding bevacizumab in ovarian cancer is reported. Bevacizumab has shown a high efficacy in the treatment of ovarian cancer. Intraperitoneal administration induces an immune activation and appears promising in the treatment of malignant ascites.