The destruction of four multi-story buildings during the last four days of the 50-day war were in breach of international humanitarian law, the group said in a report.
"All the evidence we have shows this large-scale destruction was carried out deliberately and with no military justification," said Philip Luther, director of Amnesty International's Middle East and North Africa programme.
"War crimes must be independently and impartially investigated and those responsible should be brought to justice in fair trials."
Evidence including statements by the Israeli military at the time indicate the attacks were "a collective punishment against the people of Gaza" designed to destroy their livelihoods, Luther added.
There was no immediate reaction to the Amnesty statement from Israeli authorities, AFP reported.
However, Jerusalem has refused to cooperate with a United Nations inquiry into possible war crimes during the conflict, accusing it of bias.
The Israeli army has launched a series of criminal investigations into incidents in the war, including the shelling of a UN school that medics said killed at least 15 people and the bombing of a beach where four children died.