The saucer-shaped aircraft is a novel aircraft adopting blend-wing-body configuration. The linear perturbation theory based on the classic flight dynamics was used to analyze the longitudinal flight qualities of the saucer-shaped aircraft under low speed conditions, and the time-domain method was applied on the longitudinal mode. The longitudinal flight qualities were given by simulation. Meanwhile, flight tests were conducted to validate the analysis results. The aerodynamic characteristics of the saucer-shaped aircraft, the conventional aircraft and the flying wing aircraft were also contrasted to discuss their similarities and differences. The results show that he saucer-shaped aircraft has a stable longitudinal mode and exhibits superior flight qualities and excellent comprehensive performances.