MEGA - SYSTEM SOFTWARE FOR ASTROMETRY A.V.Devyatkin and V.V.Nickiforov Pulkovo Observatory, Saint Petersburg, 196140, Russia MEGA is designed for scientific research in astrometry. MEGA can be used for processing of the astrometric observations of stars and Solar system bodies: calculations of stars and pla- nets positions, refraction corrections, phases corrections of planets, etc. Also MEGA contents the unit for interpretation of eclipses and mutual events of Saturnian satellites. This system software includes mathematical apparatus and original graphics system MEGAGRAF. MEGA system workes at IBM compatibles computers and requires 15.0 Mb of hard disk space with initial data.