A Victorian magistrate is not well enough to appear in court to face sexual assault charges, his lawyer says.

Simon Mitchell Cooper, 55, was charged on Wednesday with six counts of attempted rape and six counts of indecent assault.

The charges date back to 1984 and 1986.

His barrister Paul Galbally told the Melbourne Magistrates Court on Friday Cooper was too unwell to appear.

"It must proceed in his absence as he's not in a fit medical state to appear today," Mr Galbally told Chief Magistrate Peter Lauritsen.

Cooper, of Brighton, had his bail extended until his next scheduled appearance on April 5.

Mr Lauritsen on Thursday said Cooper would be suspended from his role until the case is resolved.

"All judicial and administrative duties that were previously assigned to the magistrate have been withdrawn and the magistrate will not be assigned any such duties until the charges are resolved," he said in a statement.

Cooper was appointed to the Victorian Magistrates Court in February last year after becoming a barrister in 1980 and serving as a crown prosecutor since 1990.

The federal government appointed Cooper as a crown prosecutor in the Solomon Islands in 2003 as part of the regional assistance mission to that country.