The objectives of this study were (1) to determine the percentage of emergency department (ED) visits due to musculoskeletal pain (MSP) by children 3-14 years of age during a period of 1 year; (2) to determine the most frequent presenting complaints; and (3) to characterize their etiology. A cross-sectional study was performed on children aged 3-14(11/12) years attended at the ED of a tertiary hospital due to MSP. The demographic and clinical characteristics of the patients were reviewed 5 days each month for 12 consecutive months. Study days were selected by computer-generated simple random sampling. Out of 4,531 visits to the ED, 826 were due to MSP (18.2 %; 95 % CI 17.1-19.4 %). When compared with children with no skeletal complaints, children with MSP had a similar sex distribution but were older (mean ± SD 7 ± 3.5 years vs 9.9 ± 3.1 years; p < 0.0001). The most common complaints were pain at the wrist (19 %), ankle (19 %) and finger (15 %). The most common etiology was trauma (88.4 %), including contusions (38 %), fractures (21 %) and sprains (18 %). Children with hip (6.7 ± 3 years; p < 0.0001) and elbow (7.8 ± 3.5 years; p < 0.0001) complaints were younger than children with pain in other locations, whereas children with wrist pain (10.5 ± 2.6 years; p < 0.002) and joint sprains (10.7 ± 2.7 years; p < 0.0001) were older. Fractures were more frequent in boys (64 vs 36 %, p = 0.008; OR 1.6; CI 1.1-2.2). Visits to the ED due to MSP increased with age. Pain at three locations represented 50 % of the presenting complaints. Trauma was the principal etiology, but fractures only represented one-fifth of the total.