In Varanasi last week, protesters threw ink on Kejriwal and a number of other party leaders during a roadshow.
On March 28, he was attacked by a man, who claimed to be a supporter of Anna Hazare, during his election rally in Haryana.
The former Chief Minister has been attacked a number of times in the past.
This was second such attack on Kejriwal in the last four days. He was attacked by a 19-year-old youth during his campaigning in Dakshinpuri area of South Delhi on Friday.
The AAP leader directed his anger at BJP after the attack.
The man slapped Kejriwal when he was shaking hands with his supporters. Kejriwal's suporters immediately thrashed the attacker, an autorickshaw driver wearing an AAP cap. He was later detained by police.
In the second attack on him in the last four days, Arvind Kejriwal was on Tuesday slapped by an unidentified man during a roadshow in Sultanpuri area of North West Delhi and the AAP leader immediately blamed BJP for it.