Ovalbumin-gallic acid-dextran (OVA-GA-DEX) conjugate was prepared by alkali grafting and dry hot Maillard reaction and its physicochemical properties and effects on the stability and antioxidant activity of resveratrol (RES) were analyzed by comparing with those of ovalbumin-gallic acid (OVA-GA) and ovalbumin-dextran (OVA-DEX). Results showed that covalent binding of GA or DEX with OVA could change the secondary structure compositions of OVA and improve its hydrophilicity and emulsification stability. The particle size distribution of three conjugates (OVA-GA, OVA-DEX and OVA-GA-DEX) in the Pickering emulsion was more uniform. OVA-GA-DEX had a smaller average particle size ((85.07 ± 10.74) nm), suggesting its better stability. The encapsulated OVA-GA-DEX can effectively protect RES from oxidation or degradation, and provide RES with higher antioxidant capacity.