Purpose This study was undertaken to compare the effectiveness of ultrasound-guided Hartmann’s solution enema (US-E) and radiological liquid enema (RX-E) in reducing idiopathic ileocecocolic intussusceptions in relation to patient age and symptom duration. Materials and methods The study group consisted of 42 patients with idiopathic ileocecocolic intussusception treated with US-E (20 patients) or RX-E (23 patients), with one patient undergoing both procedures owing to recurrence. Patients were divided into subgroups according to age (<6 months, 6–12 months, >12 months) and symptom duration (<12 h, 12–24 h, >24 h). Results Complete reduction was achieved in 15/20 patients treated with US-E (75%) and in 10/23 treated with RX-E (43.5%) ( p =ns). Recurrence was observed in 1/20 US-E and 0/23 RX-E ( p =ns) patients. No complications were encountered. US-E had a significantly higher success rate than RX-E in patients >12 months ( p =0.0063) and with symptom duration >24 h ( p =0.0361). No differences were found in the other subgroups ( p =ns). Conclusions US-E and RX-E are procedures of comparable value and safety in reducing idiopathic intussusception. US-E seems to be more effective in patients >12 months or with symptom duration >24 h. As US-E avoids radiation exposure, it should be considered the first-choice procedure for reducing idiopathic ileocecocolic intussusception, particularly in these two subgroups of patients.