Aim of this research was to assess gelling properties and riboflavin delivery capacity of mung bean protein (MBP)-sugar beet pectin (SBP) hydrogels by duo-induction of heat and laccase. The results showed that hydrogel properties were regulated by SBP concentration. When SBP concentration was 0.20%, composite hydrogel had the highest stress (665.27 ± 26.36 Pa), water holding capacity (WHC) (75.68 ± 0.88%), storage modulus (G′) and surface hydrophobicity (H0) (9550.50 ± 33.86) (P < 0.05). At the same time, network structure of composite hydrogel was the densest and system was the most stable. When SBP concentration was 0.20%, composite hydrogel had better swelling rate, riboflavin encapsulation efficiency (51.81 ± 2.31%), cumulative release rate, biological accessibility (37.83 ± 0.90%) and storage stability (P < 0.05) compared with low concentration SBP. The introduction of SBP triggered the transition of riboflavin release mechanism to non-Fick release mechanism and transported riboflavin to the colon effectively. This study might provide theoretical support for the interaction between proteins and polysaccharides in composite hydrogel system as well as provide theoretical basis for composite hydrogel to be a delivery vehicle for bioactive substances.