A reverse osmosis separation membrane, comprising a porous support, a separation active layer formed on the supporting layer, and a ultra hydrophilic layer formed on the separation active layer,
- the ultra-hydrophilic layer comprising a complex metal oxide including at least one metal element selected from the group consisting of Ti(IV), Zr(IV), Sn(IV) and Al (III), and Si;
- and an organic compound containing a hydrophilic group making a physical or chemical bond with Ti(IV), Zr(IV), Sn(IV) or Al(III) among the complex metal oxide.