Joseph Costello (born 13 July 1945) is an Irish former Labour Party politician who was a member of Dublin City Council from 2019 to 2023.

[3] In 1985, along with Tony Gregory and Christy Burke, Costello was arrested for protesting alongside market traders against casual trading legislation that had been introduced; he spent a week in prison.

[5] He was a member of Dublin City Council from 1999 until the end of the dual mandate led to him passing the seat to his wife Emer Costello.

At a Sinn Féin organised boxing charity fundraiser on 15 February 2014, Costello and his wife took a photo with gangland criminal Gerry Hutch.

On 14 February 2016, 16 days before the 2016 general election (in which Costello was a candidate), the Irish Daily Mail published an article titled "Hypocrisy", calling Costello a hypocrite for condemning gang violence after the death of Edward Hutch (Gerry Hutch's brother) but being seen in a photograph with gang leaders.

[11] In May 2019, the case was settled and the Irish Daily Mail read out an apology to Costello and his wife in court.

[11] In October 2015 on the "Saturday with Claire Byrne" RTÉ radio show, Costello mistakenly referred to Nicky Kehoe (a one-time Provisional IRA member and the Sinn Féin director of elections) as the "IRA's former chief of staff in Dublin" but made sure not to name him.

Byrne did not intervene and Sinn Féin member, Eoin Ó Broin began defending Kehoe, accidentally naming him.

Costello told The Irish Times that he worried about the right wing and anti-immigrant sentiment being allowed to build in certain communities.