Kidney bean is widely cultured and consumed in many areas of the world. The effects of preheating kidney bean protein on transglutaminase-induced cross-linking and functional properties of myofibrillar protein isolate (MPI)/kidney bean protein isolate (KPI) mixtures were investigated. SDS-PAGE displayed disappearance of original bands and occurrence of macromolecule bands, showing that the cross-linking reaction took place between MPI and KPI mixtures. The functional properties of preheated KPI/MPI mixtures could be significantly enhanced with transglutaminase treatment. The maximum storage modulus G′max of preheated KPI/MPI mixtures increased from 29.2 to 43.6 Pa, and the emulsifying activity index increased from 74.14 to 78.29 m2/g. Moreover, the gel hardness of chicken meatball was improved from 362.119 g to 720.567 g with both KPI being preheated and the addition of transglutaminase, which efficiently compensated for the decline caused by the addition of untreated KPI. The study is of significance in providing theoretical basis for adding kidney bean protein as non-meat protein into meat products.