Abstract: The characteristics of reservoirs and crude oil, way of drilling and completion at Chenbei and Suizhong 36-1 oilfield have been briefly introduced in this paper. After analyzing the causes of oil well plugging, the in-situ remedial operation tech-niques have been studied. A chemical agent called YS-01 a-gainst organic scales has been developed and used field test. Re-sults show that the plug remover YS-01 is very effective in elim-inating organic scale damage existed in the near well region, and has remarkable production stimulation. The average life span of nine wells after remedial treatment has exceeded 200 days and
acquired great economic benefits. The successful application will be very nutritious to well surveillance, plugging causes analysis, well operation technology, development of plug remover, well selection for plugging removal and remedial treatment in similar oilfields of Bohai bay.

Key words: Chenbei oilfield, Suizhong oilfield, oil well, construction technology, plug remover