Dr Kamal arrived in Sylhet on Tuesday on the eve of the rally and offered prayers at the shrine of Hazrat Shahjalal.
He said the rally aimed to get the people behind their demand of fair general elections.
“We want fairness of elections, good governance ensured through a national unity,” Dr Kamal told the media.
The Front would explain its goals and stance in the rally, scheduled to start at 2pm on the Registry Office premises of the northeastern city, according to him.
BNP Standing Committee Member Khandaker Mosharraf Hossain told bdnews24.com they were expecting a huge crowd in the rally.
Many senior leaders of the party had already arrived in the city for the rally while the others were expected by Wednesday morning.
Nagorik Oikya Convenor Mahmudur Rahman Manna told bdnews24.com that they would raise their seven-point charter of demand in the rally.
Those demands include release of jailed BNP chief Khaleda Zia and dissolution of parliament before holding the general elections with a non-partisan government in power.
Dr Kamal will be chief guest while BNP Secretary General Mirza Fakhrul Islam Alamgir will be the key speaker in the rally to be presided over by BNP leader and Sylhet Mayor Ariful Haque Chowdhury.
The Awami League has welcomed the Front, but criticised Dr Kamal for forging alliance with Tarique Rahman, the acting BNP chief convicted of money laundering, corruption and masterminding the deadly Aug 21, 2004 grenade attack targeting Prime Minister Sheikh Hasina.
The ruling party, which has rejected the Front’s demands, announced a campaign on the government’s development work through distribution of leaflets among the people near the venue of the Oikya Front rally.