pply projects on the different line modes in brief. Third, it carries on the calculation and analyses towards the reliability and economy of the different line modes of electric , describing drafts according by the calculation. Then it makes analysis and discussion on the number of optimization subsection. At last, the article make conclusion on the economy and reliability of different line modes, as well as, its application situation. Accordion to the actual circumstance, the thesis puts forward the beneficial suggestion on the programming and construction of the l0 kV electric in all areas in foshan. Providing the basic theories and beneficial guideline for the programming design of the lOkV electric and building upa , reasonable layout, qualified safe and efficiently-worked electric .