This paper presents the preparation and characterization of novel temperature‐ and pH‐responsive linear polymers and hydrogels produced from N‐acryloyl‐N′‐alkylamide derivatives of both L‐glutamic acid and L‐aspartic acid, which have the potential to act as intelligent drug carriers. The hydrophilicity–hydrophobicity balance of the linear polymers was controlled through the appropriate selection of N‐alkyl groups at C‐terminal amide sites to induce reversible transformation between water‐soluble and insoluble state with pH or temperature changes. The lower critical solution temperature (LCST) required for this transformation increased with increased pH in the solution of linear polymers. This was due to the dissociation of residual carboxyl groups, which makes the chains hydrophilic and enhances the electrostatic repulsion between their anionic residues. Low crosslinked hydrogels comprised of N‐acryloyl‐L‐glutamic acid N′‐propylamide showed reversible swelling and shrinking with temperature changes at a particular pH. These hydrogels experienced greater swelling due to local dissolution of the interior polymer chains at temperatures lower than the LCST of their corresponding linear polymers. The hydrophobic surface was also formed to restrict to release absorbed water into the polymers toward their outer phase when shrinking at temperatures higher than the corresponding LCST.