A shoe hurled at Pakistan Tehreek-i-Insaf (PTI) leaders during a rally in Gujrat on Tuesday hit party leader Aleem Khan.
According to Geo footage, the shoe directly hit the Aleem Khan when Imran was addressing the gathering during membership campaign in the city.
Imran, who appeared to have not noticed that the incident happened, remained safe. It was not clear whether the attacker wanted to hit Imran or Aleem Khan.
While Imran Khan's party blame the ruling Pakistan Muslim League-Nawaz (PML-N) for the "shameful act", Punjab Law Minister Rana Sanaullah was quick to condemn the incident, saying that such shameful stunts can never be encouraged.
The incident - the third such attack on politicians in the span of a week - took place during a public gathering of PTI workers in Gujrat.
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.
A day prior to that, on Saturday night, a man threw black ink on the face of Foreign Minister Khawaja Asif during a PML-N workers convention in Sialkot. A man was arrested after the incident.