Over the past few decades, researchers and clinicians have dedicated significant attention to fascial tissues. Current interest focuses on their anatomical and pathophysiological features. Breakthroughs in ultrasound (US) and magnetic resonance imaging (MRI) have enhanced our ability to study the dynamics and alterations of the tissue structures. However, a microscopic perspective is also essential for a comprehensive understanding of some pathologies of the fasciae. The aim of this study was to investigate, using a cadaveric study: (1) the ease of visualization of the landmarks used for the US‐guided fascial core needle biopsy (CNB); (2) the consistency and accuracy of needle placement inside fascial layers using US guidance and confirmed by histological examination; (3) inter‐rater reliability. We assessed the feasibility of US‐guided CNB in different topographical regions of human cadavers: the thoracolumbar fascia (TLF), fascia lata (FL), and crural fascia (CF). The results, confirmed by histological examination, revealed no significant difference in needle placements between the in‐plane approaches in the long and short axes for all locations and fasciae studied (long axis: 91.88%; short axis: 96.22%); p > 0.05. US‐guided core needle biopsy with the in‐plane approach is feasible, consistent and reliable. It could provide most or all of high‐quality fascial tissue samples required for pathological examination. It could also reveal changes in fascial pathologies, capturing the exact site of pathology thanks to US guidance, in particular in patchy diseases such as eosinophilic fasciitis.