The diplomats were on their way to the resort town of Sharm el-Sheikh, where several world leaders will gather on Monday for talks about the situation in Gaza.
In total, five Qatari diplomats and an Egyptian chauffeur were in the car at the time of the accident. The two diplomats who survived were injured. How the chauffeur was affected is unclear.
Qatar's embassy in Egypt's capital Cairo expresses "deep sorrow and dismay" over the incident.
"The deceased and injured will be taken to Doha with a Qatari plane today", the embassy stated in a statement during the night towards Sunday.
Among others, US President Donald Trump, UK's Prime Minister Keir Starmer and UN's Secretary-General António Guterres will participate in Monday's summit in Sharm el-Sheikh.
Qatar is one of the countries that has mediated between Israel and terrorist-stamped Hamas.
