This study investigated the effects of different concentrations of egg white protein (EWP) on the formation and properties of MP-EWP composite gels, systematically analyzing their structural changes, molecular interactions and gel network. Fourier transform infrared spectroscopy and intrinsic fluorescence spectroscopy revealed that moderate EWP addition (1.5 %) facilitated the unfolding of MP molecules, inducing conformational changes that exposed hydrophobic groups and sulfhydryl sites. The intermolecular force analysis showed that EWP addition primarily enhanced the hydrophobic interactions and disulfide bond formation, stabilizing the gel three-dimensional matrix. The composite gels formed at 1.5 % EWP exhibited peak storage modulus (G'), reflecting the optimal gel elasticity and structural integrity. Additionally, the composite gel achieved a water-holding capacity of 89.14 % and a gel strength of 4.9 N × mm, along with a dense and homogeneous gel network with reduced pore size. However, excessive EWP (>
1.5 %) led to large aggregates accompanied with enhanced phase separation and disrupted gel uniformity, as evidenced by the increase in free water content observed through low-field nuclear magnetic resonance. These findings offer valuable insights into the role of EWP in modulating MP-EWP gel formation and properties, providing practical guidance for developing high-quality eel-based gel products.