Revelations that a Latrobe Valley man fathered four children with his daughter over 30 years have rocked Victoria a day after the Ombudsman slammed the state's record on child protection.

The man, in his 60s, is charged with multiple counts of rape and incest in a case that echoes Austria's Fritzl incest horror.

According to reports, the man raped his daughter almost daily for 30 years and fathered her four children.

The man, who cannot be named, was initially charged with 83 offences, most of which have been withdrawn by police.