Wildlife introduction is an important way to maintain the long-term survival of endangered species. Monitoring the effectiveness of releasing efforts can contribute to the scientific and efficient management of species. This study analyzed the population size and distribution of the red deer in the Huangnihe forestry area of south Zhangguangcai Mountain, Jilin Province, using the noninvasive capture-mark-recapture method. The effectiveness assessment on introduction was conducted through parentage identification and genetic diversity analysis using information of fecal DNA. The results showed that: (1) The average population of red deer in the Huangnihe was 90 (range: 68-124), with a density of 0.045 (range: 0.034-0.063) individuals/km², concentrated in the northern Huangnihe and exhibiting status of geographic isolation; (2) The sex ratio within the wild deer population was 1.71 ∶ 1, and added the released ones was 1.83 ∶ 1, enhancing the population's reproductive probability with the female red deer added; (3) Parentage identification detected successful reproduction in the wild by a released individual (R3) which produced offspring; (4) Genetic diversity results suggested that 2.9 "new" allele genes were introduced to the wild red deer, thereby increasing its genetic diversity. Our research results showed the contributions of the released success on density and breeding rate. However, the behaviors, home range, and habitat occupancy should be analyzed in the future to provide more evidences on introduction effectiveness of red deer.