Marina Nalesso, 44, a presenter on TG1 in Italy, told a magazine reporter that she is religious and also wanted to witness to Christ while on air.
Besides a crucifix, she has also often appeared on television wearing holy medals with the image of Jesus or the Virgin Mary.
Nalesso is originally from Venice but is currently based in Rome.
Radical politican Silvio Viale said she should not wear a crucifix on air because TG1 is a public and secular television station, "not TG Vatican".
TG1, or TeleGiornale 1, is the main news channel of Italy's state-owned Rai 1 broadcaster.
Viale complained of Nalesso's "arrogance" at wearing the religious symbol and tweeted that she "is not paid" to witness to her Christian faith on air.
She wrote on Facebook that she wished to show "solidarity" with Nalesso.
"This is absurd," she wrote. "Christianity is part of our culture and of the history of Italians and Europeans."
Anyone who is annoyed by a crucifix should go and live somewhere else, she added.
"Most of the values that underpin our civilisation are contained in that crucifix: a symbol that represents a wealth to all of us, that we are proud of and that we want to continue to defend."