Abstract: Establishment of Einstein＇ equation of gravitational field without matter is reviewed. The guide idea and method of establishment of Einstein＇ equation of gravitational field are introduced. Newton＇ s approach of equation of field and perihelion precession of Mercury are discussed.

Key words: line of short distance, metric tensor, contact liaison, curvature tensor, equation of gravitational field, Newton＇ s approach of equation of field, perihelion precession