The invention relates to an outdoor guyed tower with automatic protection and adjusting functions. The guyed tower comprises a base, a tower body, a platform, a lightning rod, two fastening mechanismsand at least two antennas. Each fastening mechanism comprises guy cables, a protection mechanism and an adjusting mechanism, wherein the adjusting mechanism comprises an adjusting box; an adjusting unit, a first piston, a first oil cylinder, a second oil cylinder, a second piston, an oil pipe and a pull ring are arranged on the adjusting box; the protection mechanism comprises a bottom plate, a side plate, a driving rod and a protection box, and a protection assembly is arranged in the protection box and comprises a cross rod, a lantern ring and two protection units. According to the outdoorguyed tower with the automatic protection and adjusting functions, the tightness of the guy cables are adjusted through the adjusting mechanisms according to the surrounding environment, the guy cables are prevented from being too tight or too loose, and the satiability of the tower body is ensured. Besides, the bottom plate can move back and forth on the guy cables through the protection mechanisms, snakes and mice on the guy cables are driven away, the guy cables are prevented from being bitten, equipment damage is avoided, and safe operation of the guyed tower is protected.