Lightning stroke to transmission lines was introduced in this paper. Modeling and implementation method of tower, corona and insulator for lightning electromagnetic transient research was discussed. Comprehensive model for study of UHVDC lightning electromagnetic transient was built, and lightning caused fault and lightning disturbance were simulated in PSCAD/EMTDC based on the model, which offered a research platform for identification of shielding failure and back striking in plusmn800 kV UHVDC transmission lines.