The invention discloses an environment-friendly non-autoclaved tubular pile water reducing agent characterized by comprising the following components in parts by weight: 10 to 20 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione / 4,6-diamino-1,3,5-triazine-2-acetic acid polycondensate, 5 to 10 parts of 7-amino-3-vinyl-3-cephem-4-carboxylic acid / 4,4'-diaminostilbene-2,2'-disulfonic acid / polyethylene glycol monoallyl ether / 4-vinylphenylboronic acid copolymer, 1 to 3 parts of 9-fluorenecarboxylic acid, 0.3 to 0.6 part of an initiator, 2 to 5 parts of plant polysaccharide and 35 to 45 parts of water. The invention further discloses a preparation method of the environment-friendly non-autoclaved tubular pile water reducing agent. The environment-friendly non-autoclaved tubular pile water reducing agent disclosed by the invention is remarkable in water reducing effect, has the advantages of low dosage, excellent plasticizing performance, no obvious negative influence on the comprehensive performance of concrete, good energy-saving and environment-friendly performance in the preparation and use processes, high reaction activity, low reaction temperatureand capabilities of effectively enhancing the compressive strength, remarkable reduction of the hardening and viscosity of the concrete and improvement of the construction performance of the concrete.