“Numsa calls for the immediate expulsion of the Israeli ambassador in South Africa, Arthur Lenk, and the recall of comrade Sisa Ngombane from Tel Aviv,” the union said in a statement.
“Israel must be politically isolated in the same way that South Africa was during apartheid.”
Israel embassy spokesman Michael Friedman said the embassy had a mandate to improve relations between Israel and South Africa.
“We will carry on doing our work on improving relations on trade, politics and other spheres of interest to both South Africa and Israel,” he said on Tuesday.
Agence France-Presse reported that the death toll in Gaza, Palestine, had risen to 192 on Tuesday due to clashes between Israel and militant Hamas members.
Local officials in Gaza reportedly said 560 homes had been destroyed, while thousands of buildings had suffered damage after a week of fighting and air strikes.
The latest surge in violence was sparked by the kidnapping and murders of three Israeli teenagers and the revenge killing of a Palestinian youth.
Numsa called for a ban on Israeli products and a full military embargo on Israel.
“We support Palestinian civil society’s call for an immediate, full military embargo on Israel.
“Products from Israel must not be sold in South Africa. This ban must immediately be implemented by the department of trade and industry.”