Chemical cross-linking of different plant protein-based meat analogues was examined based on protein solubility of 8 different buffer solutions. The specific chemical bond and their interactions were further analyzed. Isolated soy protein (ISP), mung bean protein (MBP), peanut protein (PNP), pea protein (PP) and wheat gluten (WG) were texturized using a co-rotating twin-screw extruder at 50% moisture content. The results showed that protein solubility of meat analogues significantly decreased after extrusion, compared to their raw materials (P<0.05). The protein solubility of meat analogues increased with increasing reagent in buffer solutions. Hydrophobic interactions, hydrogen bonds, disulfide bonds and their interactions were found in the structure of meat analogues. The highest amount of covalent bond was observed in PP-meat analogues followed by ISP, WG, PNP, and the lowest MBP-meat analogues. The study demonstrated that PP are valuable raw materials for the development of meat analogue, which could promote high cross-linking bonds.