Retroperitoneal sarcoma is a rare but highly malignant type of soft tissue tumor, and its diagnosis and treatment have long been focal points in clinical research. In December 2021, the Japanese Society for Sarcoma Research, together with several other medical organizations, published the Clinical practice guidelines for the management of retroperitoneal sarcoma, which were revised in April 2023. The guidelines provide recommendations on three key aspects: the diagnosis of retroperitoneal tumors, treatment of primary retroperitoneal sarcomas, and management of recurrent or unresectable cases. They also address 11 clinical questions derived from these topics and, for the first time, present a systematic diagnostic and treatment algorithm for this disease—offering important reference value for standardizing the management of retroperitoneal sarcoma in China. The diagnostic process includes assessment of clinical features, imaging evaluation, pathological diagnosis, and biopsy. Despite the technical challenges, surgical resection remains the mainstay of treatment, with a particular emphasis on achieving R₀ resection. In addition, chemotherapy, radiotherapy, particle therapy, and targeted therapy also play crucial roles. This article focuses on analyzing and discussing the guideline's recommendations on imaging, pathological diagnosis, and surgical resection, in comparison with other domestic and international guidelines. It further explores the effectiveness of current non-surgical treatment strategies based on recent advances in particle and immunotherapy, and looks ahead to the prospects of improving patient outcomes through personalized treatment, multimodal therapy, and multidisciplinary collaboration.