Background: Charcot–Marie–Tooth disease (CMTd) is the most prevalent inherited peripheral neuropathy, often associated with foot deformities and gait and balance impairments. While the structural characteristics of the foot have been extensively investigated, limited data are available regarding the features of the plantar fascia in individuals with CMTd. Aim: To investigate the ultrasound (US) structural characteristics of the plantar fascia in subjects with CMTd and to explore their relations with disease severity and functional outcomes, encompassing lower extremity function, gait, and balance. Methods: A total of 26 individuals with confirmed CMTd underwent clinical and functional assessments. Bilateral ultrasound examination of the plantar fascia was performed to assess thickness, echogenicity, fibrillar pattern, and inflammatory signs (as assessed by US Power Doppler). Correlations between ultrasound findings, clinical data, and functional measures were also evaluated. Results: No pathological increase in plantar fascia thickness was observed, although a significant side-to-side difference was noted (p = 0.031) on ultrasound (US) imaging. No inflammatory signs were also detected. Significant associations were found between fascial alterations and age (p = 0.024), disease severity (CMTES, p = 0.014), and functional performance (10 MWT p = 0.017; SPPB p = 0.039). Conclusions: In individuals with CMT, plantar fascia abnormalities likely reflect chronic structural degeneration rather than acute inflammation. These changes are more evident with an increase in age, disease progression, and functional decline, suggesting the role of US imaging as a valuable tool for clinical and therapeutic strategies.