Fascioliasis, a food-borne trematodiasis, is a disease primarily identified in livestock, such as sheep and cattle. Human fascioliasis has been reported sporadically in Korea, but a recent increase in patients has been associated with a green vegetable juice delivery service. We aimed to investigate the serological and radiological findings of the patients treated for fascioliasis. Patients with peripheral eosinophilia, which is a positive antibody for Fasciola hepatica (F. hepatica) and liver abscess, were considered to have fascioliasis and were treated with triclabendazole at a dose of 10 mg/kg, administered twice. A total of 21 patients diagnosed with fascioliasis were included. Patients were categorized into the early and late diagnosis groups according to the time gap between the presentation and diagnosis. A comparison of initial magnetic resonance imaging (MRI) between the two groups revealed a filling defect of the bile duct that was more commonly observed in the late diagnosis group (72.7% versus 0%; P = 0.003). Hepatic abscess lesions resolved slowly, with 14.3%, 50%, and 85.7% of patients showing complete resolution on computed tomography 6, 12, and 24 months after treatment, respectively. The mean levels of anti-F. hepatica antibodies decreased after a 6-month follow-up (mean levels, onset versus 6-month, 12-month, or 24-month follow-up; 4.36 versus 3.29, 3.17, or 2.31, respectively; all P <0.01). Eosinophil counts reduced significantly 1 month after treatment and remained normal thereafter in both groups. This study suggests that MRI could be useful for diagnosing fascioliasis in a subgroup of patients and that hepatic abscesses and positive antibody results could last for several months after treatment.