The invention discloses a coiled 
reverse osmosis membrane element, which is formed by winding at least one group of water purification membranes on a central water yielding 
pipe, wherein the water purification membrane group consists of a 
purified water guide net, a 
reverse osmosis membrane and a water inlet guide net which are overlapped; a water 
inlet flow channel is formed by folding the inner surface of the 
reverse osmosis membrane, and a water yielding flow channel is formed between the adjacent outer surfaces; the water inlet guide net is positioned in the water 
inlet flow channel; the 
purified water guide net is positioned in the water yielding flow channel; the water yielding flow channel only has a 
purified water outlet facing the central water yielding 
pipe, and other three sides of the water yielding flow channel are closed and sealed; the partial zones, far away from the central water yielding 
pipe, on the two sides, adjacent to a folded side, of the water 
inlet flow channel which are closed and sealed; so a small section 
raw water inlet is formed on the two sides close to the central water yielding pipe respectively and a thick water outlet is formed on the side of the water inlet flow channel opposite to the folded side. Through improvement, the reverse 
osmosis membrane element of the invention increases the 
water velocity on the surface of the membrane, reduces the 
concentration polarization on the surface of the membrane, and reduces the 
pollution speed of the coiled membrane element so as to prolong the service life of the membrane element.