The leaders of the Armenian National Congress (ANC) opposition bloc arrived at Liberty Square, where about 1500 people have gathered.
The regular rally is expected to kick off soon, a PanARMENIAN.Net correspondent reported from the ground.
During the September 30 rally, ANC leader Levon Ter-Petrossian announced the start of a series of round-the-clock protest actions to last 7 days.
According to Haykakan Zhamanak daily editor-in-chief Nikol Pashinyan, 1500 people remained in the square overnight, although witnesses estimate the number at 200-300.