As Imran Khan was addressing the crowd atop a vehicle, a shoe came flying and hit PTI leader Aleem Khan, who was standing right next to Imran Khan, Dawn reported.
The attacker was overpowered by the crowd.
Soon after the attack, Imran Khan concluded his address.
On Sunday, an Islamic seminary student hurled shoes at ousted prime minister Nawaz Sharif during a function at the Jamia Naeemia seminary in Lahore's Garhi Shahu area. Three suspects were arrested after the episode.
On Saturday, a religious extremist blackened the face of Foreign Minister Khwaja Asif with ink during a PML-N workers convention in Sialkot. A man was arrested after the incident.