<p>This paper is concerned with the orbital stability of solitary waves in the mKdV-Schrödinger system with cubic-quintic nonlinear terms through detailed spectral analysis and abstract stability theorem. First, we derived the explicit solitary wave solutions by assuming the solution expression. Then, through using the orbital stability theory developed by Grillakis et al., we established general criteria for assessing the orbital stability of solitary waves of this system.</p>