The threatening social media post by the dissident-linked republican organisation posted personal details of the journalist, adding a call to not engage with her in future.
Mr Dickson said the threat undermined freedom of the press.
“Freedom of the press is one of the most valuable facets of any democracy. Journalists must be allowed to carry out their vital job, which is a fundamental scrutiny role. I give my full backing to the National Union of Journalists, who carry out great work on behalf of their members dealing with threats such as this.
“Many local journalists have carried out great investigative work, particularly lately into several scandals throughout Northern Ireland. This threat must be removed immediately and I call on this organisation to do so without delay.”