Abstract: A serial of poly(acrylamide-co-diacetone acrylamide) (PAM-co-PDAAM) copolymers were synthesized by radical polymerization from acrylamide(AM) and diacetone acrylamide(DAAM). The structure of PAM-co-PDAAM was characterized by Nuclear Magnetic Resonance spectroscopy(¹H-NMR) and Gel Permeation Chromatography(GPC). Resorting to the acylhydrazone dynamic covalent bonds between hydrazides and carbonyl group of ketone, the hydrogel with pH-responsive sol-gel transition was formed by mixing PAM-co-PDAAM and adipic dihydrazide (ADH). The sol-gel transition was studied by rheological measurement, Scanning Electron Microscope (SEM) and Fourier Transform Infrared spectroscopy (FT-IR). Effect of the compositions of copolymers on the lowest mass fraction for hydrogel formation was studied. Results demonstrated that the higher composition of DAAM, the lower mass fraction for hydrogel formation. Besides, the hydrogel exhibited self-healing property.