An explosion occurred early Saturday in Giza's 6 October City district, causing the death of a girl and injuring her parents, Al-Ahram Arabic website reported.
The explosion targeted a call centre under construction.
Preliminary reports state that unknown assailants planted a bomb in the building that caused the death of the daughter of the watchman, leaving him injured along with his wife.
The head of Giza's security directorate arrived to the scene of the explosion along with security forces to examine the area.
This is the first Egyptian civilian casuality and the second since the Sinai tourist bus attack in February that killed four including three South Korean tourists.
On Wednesday, a series of makeshift bombs exploded in different parts of the capital Cairo, injuring at least six.
The blasts came after weeks of relative calm since a spike in militant attacks following the army's July ouster of Islamist president Mohamed Morsi amid mass protests against his rule.
Most of the attacks, mainly targeting security forces, were initially focused in the sparsely populated Sinai Peninsula but spilled over into other cities, including Cairo and the Nile Delta.
According to a government tally, the violence has killed at least 500, mainly policemen and troops.
Former army chief Abdel-Fattah El-Sisi, who led Morsi's ouster, was sworn in as Egypt's new president earlier in June after he won a landslide election victory.