The U-S and Australia were the only members of the UN Human Rights Council to vote against an investigation into the deaths of more than 50 Palestinians in just 24 hours.
Labor frontbencher Anthony Albanese has urged the government to explain its stance.
In a statement to SBS News, Ms Bishop says the resolution failed the "test of balance and impartiality", adding that it did not refer to the role of Hamas in inciting violent protests.
She says the proposal pre-judged the outcome of the inquiry and the potential violations of international law.
