The main opposition Republican People's Party (CHP) in Turkey has been engulfed by a prolonged internal crisis, triggered by the imprisonment of its leading presidential hopeful, Istanbul Mayor Ekrem İmamoğlu, and culminating in a disputed leadership battle.

Since the March 2024 local elections, the CHP has seen internal turmoil, with Daily Sabah reporting on February 12, 2026, that 30 mayors and 66 municipal council members had resigned, with critics citing pressure from party leadership and a lack of tolerance for dissent.

On March 2, the CHP launched its 2028 election campaign at a convention. Imprisoned former Istanbul mayor Ekrem İmamoğlu appeared via AI, and the party called for an early election despite lacking parliamentary power. İmamoğlu, arrested in March 2025 on corruption and terrorism-related charges, is widely seen as President Recep Tayyip Erdoğan's main challenger. In a statement reported by the South China Morning Post on March 8, İmamoğlu said an irreversible process for change had begun and could not be stopped by the government or judiciary.

On March 9, İmamoğlu's mass trial began outside Silivri prison, with over 400 defendants including 105 in pre-trial detention. As reported by The Guardian and Deutsche Welle, prosecutors sought a prison term of more than 2,000 years on charges of leading a criminal organization, tender-rigging, bribery, and money laundering. İmamoğlu clashed with the judge, and critics called the case politically motivated to block his presidential candidacy. On March 11, CHP leader Özgür Özel said the trial was "purely political," aimed at blocking İmamoğlu's challenge. On March 15, Özel proposed placing İmamoğlu under house arrest. On March 18-19, thousands rallied in Istanbul to support İmamoğlu on the anniversary of his arrest, with Al-Monitor and Deutsche Welle reporting large crowds. RIAN reported that the rally featured chants against "American imperialism" and calls for early presidential elections. On March 26, internal dissent against Özel emerged within the CHP, with around 40 deputies criticizing his policies. In April, Özel intensified his push for snap parliamentary elections, meeting the pro-Kurdish DEM Party on April 6, though the ruling AK Party and its ally MHP dismissed the proposal. On April 7, Der Spiegel reported that prosecutors launched a new investigation into İmamoğlu for allegedly insulting a public official after he told the court that only one criminal organization existed — the prosecution. On the same day, reports emerged that the CHP faced a potential split, with Özel and İmamoğlu possibly forming a new party. Former CHP chair Kemal Kılıçdaroğlu, who led the party for over a decade, was urged by dissidents to return. On April 14, Kılıçdaroğlu received an 11-month, 20-day suspended prison sentence for insulting Erdoğan in 2013.

The crisis deepened dramatically on May 24, when Turkish riot police stormed the CHP headquarters in Ankara, using tear gas and rubber bullets to evict Özel and his supporters after a court annulled the November 2023 party congress that brought Özel to power, citing irregularities including vote-buying allegations. The court reinstated Kılıçdaroğlu as interim chair. The South China Morning Post and Time reported the eviction as politically motivated to undermine the opposition. On May 26, police used water cannon and tear gas to disperse an Izmir rally supporting Özel, as reported by The Guardian and Deutsche Welle. Both rival chairs held separate rallies on May 30-31. Özel drew thousands in Ankara, calling for an immediate extraordinary party congress, while Kılıçdaroğlu addressed supporters at party headquarters, pledging to purge corruption. On June 1, Kılıçdaroğlu formed a new administrative committee, while the Istanbul Chief Prosecutor's Office requested financial records of delegates from the disputed 2023 congress, with two individuals confessing to bribing delegates for Özel, according to Daily Sabah on June 2. On June 3, Özel appealed the court ruling to the Supreme Court of Appeals and vowed to continue the fight, while the CHP disciplinary board convened on June 4 to consider expelling senior members loyal to Özel. Kılıçdaroğlu stated that the party would hold a congress once a court injunction was lifted.

On June 5, a Turkish court formally removed Özgür Özel as CHP chair and reinstated Kılıçdaroğlu, who was described as a "traitor" by some within the party, according to Der Spiegel.