A simple and efficient protocol for in vitro plant regeneration through somatic embryogenesis was developed in four Lilium cultivars. Roots from in vitro seedlings of four lily cultivars were cultured on Murashige and Skoog (MS) medium (1962) supplemented with the auxin picloram (PIC) used alone (0.5, 1.0, and 2.0 mg l^-1) or in combination with the cytokinins BAP or TDZ at 0.5 mg l^-1. Picloram with the combination of cytokinins was found to be positive to improve the callus formation. Generally speaking MS medium supplemented with 1.0 mg l^-1 PIC and 0.5 mg l^-1 BAP gave the highest percentage of explants forming callus in three Lilium cultivars (‘Kankado’ = 95.7%; ‘Manissa’ = 98%; ‘Siberia’ = 80%); for ‘Sorbonne’ the best performance for callus formation was scored on MS medium + 1.0 mg l^-1 PIC and 0.5 mg l^-1 TDZ (88.7%). Embryoids regeneration occurred after a subsequent transfer onto fresh medium and a further one month of culture. The number of embryoids per 0.1 g of callus ranged from 11.7 (‘Siberia’ on MS medium + 1.0 mg l^-1 PIC and 0.5 mg l^-1 TDZ) to 70.3 (‘Manissa’ on MS medium + 1.0 mg l^-1 PIC and 0.5 mg l^-1 BAP). The callus induction efficiency, callus growth index, callus growth intensity, and numbers of embryoids induced from 0.1 g of callus of root were higher than that of bulb scales and leaves. Embryoids cultured on MS medium with 0.1 mg l^-1 CPPU developed into complete plants.