To investigate the predictive factors of success or failure in treating ectopic tubal pregnancies with two-dose methotrexate (MTX).The records of patients treated for tubal EP with two-dose MTX were retrospectively reviewed. Patients were divided into two groups; the Group-I (failure) consisted of patients who did not respond to MTX therapy and the Group-II (success) included patients who were successfully treated with MTX. Parameters, including the week of gestation, presence or absence of fetal cardiac activity, gestational sac size, serum β-hCG levels, and adverse effects were compared.Fifty patients were included in this study, 8 (16%) were in Group-I and 42 (84%) were in Group-II. Patients in Group-I required surgery after a mean duration of 6.7±3 days after administering the initial dose of MTX. There was no difference between the groups in terms of the week of gestation, presence or absence of fetal cardiac activity, gestational sac size, serum β-hCG levels, and adverse effects. The average time to β-hCG negativization was 31 days in Group-II.The two-dose MTX protocol has a reasonable success rate, which seems to be dependent on serum β-hCG levels.