Venous thromboembolic events (VTE) in children are frequently associated with central venous lines (CVL). Identifying risk factors related to CVL management could potentially minimize CVL-related thrombotic complications. The objectives of the study were to assess whether CVL location, type, size, and duration of placement are associated with the incidence of VTE in children. The study was a prospective, multicentre cohort study in a general pediatric population requiring CVL. Data on CVL characteristics were documented prospectively using standardized case report forms. Outcome assessments were by i) clinical monitoring for symptomatic VTE which were confirmed by appropriate objective test, or ii) screening by venography at study exit. Among 158 children, 21 (13%) hadVTE. The incidence of VTE was increased with femoral CVL (32%) and subclavian CVL (27%) compared to brachial CVL (12%) and jugular CVL (8%; p = 0.01). The incidence of VTE was independent of CVL type (peripherally inserted central catheters, untunneled CVL, tunneled exteriorized CVL, subcutaneous ports; p = 0.90), and CVL size (CVL diameter, p = 0.42; number of CVL lumen, p = 0.58). The incidence of VTE did not increase with duration of CVL placement: 0-5 days (17% VTE), 6-20 days (19%), 21-35 days (10%), and 36-50 days (11%, p = 0.68). The incidence of CVL-relatedVTE may be reduced by preferred placement of CVL in brachial or jugular veins. The choice of CVL type and size does not significantly influence the risk of VTE. Short-term CVL are associated with a similar risk of VTE as longer-term CVL.