More than 800 Brothers have been arrested in the current crackdown
Egypt's opposition Muslim Brotherhood group says it will boycott municipal elections after being allowed to field 20 candidates for thousands of seats.
Deputy leader Mohammed Habib urged people not to vote in protest at the government's "disregard for justice".
The authorities have carried out a wide-ranging crackdown ahead of Tuesday's vote, leaving many candidates behind bars or unable to register.
International groups have condemned the crackdown against the opposition.
President Hosni Mubarak's ruling National Democratic Party has candidates for all 52,000 seats, and will be unopposed in 90% of them, party sources say.
Correspondents say Egyptian municipal elections are rarely marked by controversy, but this year's poll is the first since a constitutional amendment in 2005 which required presidential candidates to secure the backing of local councillors.
Other opposition groups complained of obstruction by the government, ranging from bureaucratic hurdles to assaults at registration stations.
More than 800 members of the Muslim Brotherhood group have been arrested in recent weeks.
The group says 2,664 of its candidates succeeded in obtaining court rulings ordering authorities to allow them to stand in the local election but the rulings were disregarded.
The Brotherhood says the government is eager to avoid another electoral setback after pro-Islamist independents won 20% of seats in the last parliament.
The group is officially banned in Egypt, although its activities have been broadly tolerated. Candidates for elections stand as independents.