The decision to keep the crossing open was taken "to alleviate the suffering" of residents in the Palestinian enclave, president of Egypt, Abdel Fattah el-Sisi said on Facebook late Thursday.
The Rafah crossing is Gaza's only gateway to the outside world not controlled by Israeli occupation, but Egypt has largely sealed it in recent years, citing security threats.
It is usually open a few dozen days a year and such an extended period is rare.
President Abdel Fattah el-Sisi announcement comes after some 60 Palestinians were killed by Israeli occupation fire on the Gaza border earlier this week, with the victims described by Egypt's foreign ministry as "martyrs".