The invention discloses a multifunctional full-effect direct drinking system, which has functions of multiple-circulation sterilization and disinfection, on-line sterilization fresh-preservation, provides water good in quality and taste, and can intensively provide lots of direct drinking water. The system comprises an electrical control device (30), as well as a raw water tank (1), a raw water pump (2), a multi-media filter (3), an activated carbon filter (4) , a water softener (5), a medicine adding device (6) for the water softener (5), a medicine cleaning device (7), a security filter (8), a high pressure pump (9), a reverse osmosis device (10) with a plurality of RO films, a purified water tank (11), an ultraviolet sterilization device (12), a frequency conversion feed water pump (13), a rear-mounted precision filter (14), a rear-mounted adjuster (15), and a net water end (16), which are connected sequentially, so as to form a direct drinking water making pipe, wherein an ozone mixer (19) and an ozone machine (18) are arranged on the pipe between the reverse osmosis device (10) and the purified water tank (11); the net water end (16) is connected with the purified water tank (11) through a backwater filtering device (17) so as to form a backwater circulation sterilization and disinfection pipeline. Therefore, the drinking system can be applied to the field of direct drinking water.