The demonstrators urged the Organisation of the Islamic Conference (OIC) to stop its assistance to Rohingya in Rakhine state, where tensions have been running high since deadly Buddhist-Muslim clashes broke out in June.
"We protested against the OIC and also Bengalis as we don't want them on our soil," organiser Nyo Aye told AFP by telephone from the state capital Sittwe.
Myanmar's estimated 800,000 Rohingya are viewed as illegal immigrants by the government and by many Burmese, who refer to them as Bengalis.
The rally came a day after hundreds of monks took to the streets of Sittwe to protest against local Muslims and the OIC's activities.
The tensions in Rakhine have spread to neighbouring Bangladesh, where police said last week they had arrested nearly 300 people in connection with a wave of violence targeting Buddhist homes and temples.