The New South Wales Attorney-General says persistent illegal graffiti artists should be jailed, but only as a last resort.

Greg Smith says graffiti crime angers the community but is one of the least investigated and prosecuted offences.

The new Coalition Government has promised to toughen anti-graffiti laws in its first 100 days in office.

Mr Smith says he plans to set up a graffiti hotline and to ensure that young offenders are treated like adults in the courts.

"I think the emphasis on jailing, I must emphasise that is only for the last resort people. The people that are just repeatedly offending, been caught and just don't seem to be learning," Mr Smith said.