Victorians are committing less crime overall but are being jailed at the highest rate since the late 19th century, a study says.

The state's imprisonment rate, which takes into account general population changes, climbed from 94.2 to 111.7 prisoners per 100,000 adults between 2002 and 2012, the Sentencing Advisory Council's study said.

The study found that the imprisonment rate rose because certain crimes punishable by imprisonment - drug offences, crimes against the person and offences against good order - had increased and also because the courts had imposed longer sentences in the past decade.

The council's chairman, Professor Arie Freiberg, said the findings challenged the public perception that courts typically imposed light sentences. ''Not only are they getting tough overall, they're getting tough on the things that most concern and alarm the population, which is offences against the person,'' Professor Freiberg said.

There were 4884 people in Victorian jails at June 30 last year.