The invention provides a field generating device of steep pulses; and the field generating device comprises an oil-immersed impulse voltage generator (1), a middle energy storage peak carburation line (2), a supporting insulator (3), a steepening clearance (4), a GIS (Geographic Information System) connecting bus (5) and a variable impedance transmission line (6). The field generating device of the steep pulses, provided by the invention has the advantages of full-sealed form, compact structure and convenience in transportation.