Chronic low back pain (CLBP) represents a prevalent clinical condition, wherein the transversus abdominis (TrA) muscle is recognized as a pivotal contributor to spinal stability and may play a significant role in mitigating pain and functional impairment. This systematic review synthesizes findings from eight randomized controlled trials (RCTs) published between 2010 and 2025 that examined the impact of TrA-targeted interventions utilizing ultrasound assessment in individuals with CLBP. The included studies, comprising sample sizes ranging from 24 to 50 participants, evaluated interventions such as core stabilization exercises, motor control training, and ultrasound- guided biofeedback, compared against control groups receiving either standard care or alternative exercise protocols. Ultrasound imaging was employed to quantify TrA thickness and activation, alongside assessments of pain intensity (VAS), disability (ODI; RMDQ; FRI), and functional performance. The aggregated results consistently indicated that interventions focused on the TrA significantly enhanced muscle thickness and activation (p<.05), decreased pain levels (VAS reductions ranging from 1.2 to 3.5 points), and improved disability indices (ODI reductions between 5 and 15 points). Notably, real-time ultrasound biofeedback and motor control training demonstrated superior efficacy relative to conventional exercise regimens, particularly in augmenting TrA activation and reducing disability scores (p<.01 in four studies). Furthermore, a preliminary study conducted with an older adult cohort indicated additional benefits associated with the use of ultrasound imaging. In summary, current evidence substantiates the effectiveness of TrA-focused training combined with ultrasound feedback in managing CLBP and supports its integration into clinical practice. Nonetheless, further large-scale, longitudinal RCTs are necessary to delineate optimal intervention parameters and to evaluate the sustainability of therapeutic outcomes.