<p>Natural polymer-based hydrogels are widely used for tissue engineering, drug delivery, food, and cosmetic applications due to their biocompatibility, biodegradability, and physical properties similar to the extracellular matrix. In this study, we develop ternary CHA hydrogels composed of low-molecular-weight collagen (Col), hyaluronic acid (HA), and alginate (Alg), three representative natural polymers, with varying calcium ion (Ca²⁺) concentrations ranging from 0.0 to 2.5 wt%. The combination of the three natural polymers imparts multifunctional characteristics, including intrinsic bioactivity, high hydration capacity, and ion-responsive gelation. The dynamic network of the hydrogels is formed by the “egg-box” coordination between Ca²⁺ and alginate, together with hydrogen-bonding interactions among Col, HA, and Alg. This Ca²⁺-induced cross-linking mechanism enables control of the swelling behavior and cross-linking density of the hydrogels. Rheological analyses elucidate that the CHA hydrogels cross-linked with Ca²⁺ exhibit a yield stress (<i>τ</i>_y), which increases with increasing Ca²⁺ concentration, followed by shear-thinning behavior beyond <i>τ</i>_y. Moreover, their storage modulus (<i>G′</i>) and loss modulus (<i>G″</i>) increase, whereas their swelling ratio and linear viscoelastic (LVE) region decrease with increasing Ca²⁺ concentration, indicating a higher ionic cross-linking density and a more rigid but brittle network. The CHA hydrogels, offering tunable mechanical properties via ionic cross-linking and inherent biocompatibility, demonstrate strong potential for drug delivery systems, regenerative scaffolds, and advanced cosmetic formulations.</p> Graphical abstract <p>CHA ternary hydrogels composed of collagen, hyaluronic acid, and alginate are fabricated with varying Ca²⁺ concentrations by forming the three-dimensional dynamic networks contributed by Ca-induced ionic coordination and hydrogen-bonding interactions among constituents. Higher Ca²⁺ content yields denser networks and higher elasticity of the hydrogels, enabling control of physicochemical and rheological properties for biomedical, pharmaceutical, and cosmeceutical applications.</p> <p></p>