Super‐hydrophilic coatings are useful in many applications such as agricultural greenhouses. However, the direct modification of super‐hydrophilic coatings on intrinsic hydrophobic surfaces is still a challenge, particularly without any pretreatment. Here, highly transparent super‐hydrophilic and waterproof coatings on intrinsic hydrophobic surfaces were prepared via layer‐by‐layer (LbL) assembly catechol‐grafted polymer‐branched poly(ethylenimine) (bPEI)‐3‐(3,4‐dihydroxyphenyl)propionic acid (denoted as C) and poly(acrylic acid) (PAA)‐dopamine (denoted as D) inspired by the mussel. The catechol‐functionalized polymer facilitates a mechanically robust coating that is tightly attached to the surface of the intrinsic hydrophobic polymers. This gives the coating excellent antifogging ability with a lowest contact angle of 0°. These coatings also demonstrated excellent stability after cross‐linking with Fe3+ or alkali species. The super‐hydrophilic and waterproof coatings on intrinsic hydrophobic surfaces can also be prepared by the spray method. The super hydrophilic coating exhibits favorable antifogging ability, making it potentially useful in numerous applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48013.