Walnut meal is rich in high-quality plant protein and dietary fiber, but its value-added use in plant-based meat products remains limited. To develop a distinctive low-fat walnut meal-based meat product, this study prepared a walnut-based plant meat analog (WPMA) and compared it with selected commercial soy-based (CSPMA) and wheat-based (CWPMA) plant meat analogs. Physicochemical measurements, texture analysis, electronic tongue analysis, gas chromatography–ion mobility spectrometry (GC–IMS), and sensory evaluation assessed product quality. Principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS–DA), and relative odor activity value (ROAV) analysis supported the assessment. WPMA had a fat content of 2.90 g/100 g and favorable structural characteristics. It also received higher mean scores for structural integrity, mouthfeel, and overall sensory quality. GC–IMS identified 63 volatile compounds, and OPLS–DA screened 28 discriminatory volatile compounds. ROAV analysis indicated that 1-octen-3-one and tetrahydrothiophen-3-one were key aroma compounds, while eucalyptol was an important aroma-modifying compound. The first two principal components explained 88.17% of the total variance, and the PCA results indicated distinct overall profiles among the three products. These findings provide a theoretical basis and technical reference for the value-added use of walnut by-products and the development of diverse plant protein-based foods.