Objective Summarize the information of 135 killing familiar cases and study the characteristics of these cases, in order to analysis the key points of the case investigation. Methods Collected the data of the 135 killing familiar homicides cases which have solved and happened in a province middle of China from 2011 to 2013. The paper analyzed the data accordding the basic information, the forensic professional, the forensic scene and so on. Results Most killing familiar cases occured between husband and wife or parents and children. The cases frequently occur in rural areas. Most of the cases occur between the adults. The killing familiar cases commonly occur in Decemember, January, Feburary, the cases commonly occur in evening(from 6 pm to 6 am). The motivate of the cases is unobvious, the murder suffer from the mental patient is commonly. In these cases, mostly tools of crime is the blunt tools and the sharp tools. Mechanical asphyxia and mechanical iniury were the most commonly causes of death in these cases. Conclusion The social characteristics of suspect, injury tool, cause of death, time of the incident in the killing familiar case showed similar general characteristics, but how collect evidence in the case is the difficulty of the case investigation.