The phenomenon of urban expansion in Southeast Asia has increased since the 1960s due the land development for the capital as well as surrounding cities supporting it. Since the 1970s, private developers in Jabodetabek have transformed rural areas into new cities and connecting them primarily via toll roads. They have developed the suburb aggressively for real estate projects, resulting in rapid urban sprawl. Most of these new cities are outfitted with amenities, including schools, hospitals, sewage systems, medical facilities, security personnel, and public parks. Some were motivated by the need for new settlements, while others were motivated by economic and industrial growth. However, the new cities have become segregated communities because they are heavily guarded, gated, and surrounded by walls. Their existence creates disparities between private cities and surrounding kampongs, which can be problematic for the surrounding society. Through literature review, mapping, interviews, and taking Bintaro Jaya as the case study, this paper analyses the characteristics of the private city in Southeast Asia and the Indonesian context as well as how gentrification resulting from land transformation has become the primary driver of urban expansion. This paper argues that the definition of Private cities cannot be generally adopted to Indonesian context.