Increasing rates of diagnosis of ductal carcinoma in situ (DCIS), given the widespread use of mammography, is a global trend. Various attempts have been made in the selection of surgical methods and application of radiation therapy (RT), and the prevalence of infectious diseases has also affected these attempts. This study aimed to investigate evolving treatment patterns and trends in the management of DCIS in South Korea. We conducted a comprehensive search of the Korean Health Insurance Review and Assessment Service-National Patient Sample (HIRA-NPS) database and selected patients who underwent breast surgery following a DCIS diagnosis between 2009 and 2020. Based on this sample, the analyses were weighted according to the Korean population. We examined annual variations in mastectomy types, reconstructive procedures, and RT utilization from a multidisciplinary perspective. In our weighted sample, 43,780 patients with DCIS underwent surgery, with a consistent annual increase of 10%. The proportion of lumpectomy procedures increased from 56.7% to 65.4%, showing a greater growth rate than that of total mastectomies (TMs). Following the availability of reconstruction data in 2015, shifts have emerged toward a preference for implant-based autologous tissue reconstruction. As we transitioned to the latter part of our study, the trend was marked by the increasing adoption of hypofractionated RT and omission of RT. Of the patients who underwent lumpectomy in 2020, 25.6% adopted hypofractionated RT and 53.8% omitted RT. This transformation was particularly evident among older patients, individuals treated in metropolitan areas, and those treated in small-sized healthcare facilities. Our study sheds light on the changing landscape of DCIS treatment in South Korea incorporating perspectives from surgeons, plastic surgeons, and radiation oncologists. We observed an increase in the rates of lumpectomy and implant-based reconstruction. Adoption of hypofractionated RT and omission of RT showed increasing trends.