The clashes took place just before Kardashian opened the Bahrain branch of her Millions of Milkshakes shop.
An Associated Press journalist saw protesters chanting "God is Great" near the shopping complex in Riffa, some 20 kilometers (12 miles) south of the capital Manama. The demonstrators were cleared before Kardashian appeared late Saturday.
Earlier, she posted glowing remarks about Bahrain on her Twitter account, calling it "the prettiest place on earth." It was re-Tweeted by Bahrain's foreign minister.
Kardashian was in Kuwait earlier this week to open another branch of the shop.