The destruction takes place about one month before the fourth anniversary of the murder will be marked.
The memorial was also set aflame on the first anniversary of the rabbi's murder.
Deputy Head of the Samaria Regional Council, Yossi Dagan, who was a close friend of Rabbi Chai, said upon witnessing the vandalism: “Only barbarians are capable of doing things like this. People who can burn and desecrate a memorial for a murdered man are not worthy of being called human.”
"We all stand with the Chai family in these difficult times,” he added. “[The terrorists] come to cut off life, and we will add life. Our response to the inhuman terrorists of the Palestinian Authority will be construction, construction and construction.”
Rabbi Meir Avshalom Chai, 40, of Shavei Shomron, was mortally wounded in the head when terrorists fired at the car he was traveling in, between the Jewish communities of Shavei Shomron and Einav in Samaria.
He left behind seven children, of whom the youngest was two months old at the time of the murder, and the oldest was 17.
The latest attack comes a day after a peaceful protest vigil in Gush Etzion, south of Jerusalem, was attacked twice in less than two days.
The vigil was declared after Arab terrorists hurled a firebomb at the car carrying the Khoury family, injuring husband and wife Zachy and Na’ama.
Zachy Khoury described to Arutz Sheva the terrifying moment he saw his wife catch fire after the molotov cocktail struck their car outside the Israeli village of Tekoa.