"Ever since 1993, every year July 21 brings back excruciating pain and agony to our memory, of the barbaric act of violence and brutal firing meted out by the previous Left Front government," she wrote on her Facebook page on the eve of the annual Martyrs' Day rally.
Nineteen years ago, 13 youths were killed in police firing during a demonstration organised by the Youth Congress, of which Banerjee was president at the time.
"The voice of democratic demand raised in a peaceful procession was stifled with bullets and violence...Every year, 21st July is dedicated to 'Sahid family' (martyrs family) belonging to different democratic movements," the Trinamool Congress supremo said.
Describing the day as "memorable and painful," she said, the martyrs' "sacrifice" had inspired and strengthened "our grit, zeal and determination to fight and to establish democratic rights and unveil the misrule of the Left Front government in the state."
She has also posted a photo album where policemen are seen beating demonstrators. One of them shows an injured Banerjee recovering in a hospital.
"Let us bow our heads down, pay obeisance and remember their invaluable sacrifice and also take a pledge to rededicate ourselves to continue to fight for the cause of 'Maa Mati Manush' and build a harmonious, peaceful and prosperous Bengal," she said.