A woman in Ipoh was told to cover up her arms before she could enter the city council building.
Miss Eunice Chai, a 32-year-old logistician, was wearing a sleeveless blouse and jeans.
She told The Star she was stopped by security guards, one of whom commented on the "lack of sleeves" of her blouse.
Miss Chai, who had gone to the city council to apply for a business licence, borrowed a jacket from a friend who was with her.
"I thought what I was wearing is considered decent since my legs are all covered up, but I didn't expect this treatment here as well," she said.
A dress code poster at the city council building shows women in long-sleeved, long-skirted traditional outfits from the main three races. Men are shown in formal shirts with sleeves, and pants.
The poster also shows that those in sleeveless tank tops, shorts, short skirts or slippers will not be allowed into the building.
It is the latest in a series of incidents in Malaysia in which people have been told to cover up.
In early June, a a Malaysian motorist, wearing a top and skirt which ended just above her knees, was told to wear a sarong or be refused service at a Road Transport Department (JPJ) office, reported The Star.
Two weeks later, two women invited to attend a press conference at a government building in Selangor were told to wear sarongs to cover up their legs or be refused entry.
A few days after that, a blogger posted about how his knee-length shorts were deemed inappropriate at Kuala Lumpur International Airport, in an incident which happened in May. KL authorities later apologised.