Ultrasound imaging plays a pivotal role in the assessment of knee pathologies, providing high-resolution, real-time visualization of musculoskeletal structures. For a thorough evaluation, the knee is divided into anterior, posterior, medial, and lateral compartments, with each region examined using proximal, mid, and distal scanning techniques. This chapter presents a comprehensive overview of knee sonoanatomy and the most commonly encountered pathologies, with a particular focus on the quadriceps tendon, suprapatellar recess, patellar tendon, and Hoffa’s fat pad in the anterior compartment. The medial compartment is explored in detail, emphasizing the medial meniscus, medial collateral ligament (MCL), medial genicular nerves, and the pes anserine tendons and bursa—all vital for joint stability and sensory function. In the lateral compartment, the evaluation includes the lateral joint line, lateral collateral ligament (LCL), lateral meniscus, iliotibial band (ITB), and popliteus tendon, all of which are frequently associated with overuse syndromes, particularly among active individuals. The posterior region highlights important neurovascular and musculoskeletal structures, such as the popliteus tendon, tibial nerve, and common peroneal nerve. By presenting a structured, region-specific scanning protocol, this chapter aims to enhance diagnostic accuracy and improve the clinical application of musculoskeletal ultrasound in the evaluation and management of knee disorders.