Abnormally invasive placenta is characterized by direct attachment of chorionic villi to the uterine wall. This adherent placenta traditionally has been managed by peripartum hysterectomy. Nowadays, there is a lot of interest toward gradual shift from traditional management of invasive placentation to conservative ones leaving the placenta in situ to avoid the surgical morbidity of hysterectomy and loss of future fertility. Administration of methotrexate (MTX), as an adjunctive antimetabolite drug, resulted in conflicting data during conservative management of abnormal placentation. This review assessed all published data on efficacy and safety of MTX therapy as conservative management of invasive placentation. Fifty-three articles including one prospective cohort study, 2 retrospective cohort studies, 10 case series and 40 case reports were identified. Conservative management has beneficial effects on the avoidance of major surgery with the consequent morbidity and the preservation of future fertility. Infection and vaginal bleeding were main complications of MTX therapy. Although MTX therapy may result in accelerated involution or expulsion of placenta and has some beneficial effects on hemorrhagic events, but there is not enough evidence on its efficacy and safety to recommend its routine uses in all cases of invasive placenta.