The rally was held by four Left parties -- CPI, CPI(M), CPM Punjab and CPI(ML)-- against the Prevention of Damage to Public and Private Property Bill 2014 passed by the Punjab Assembly.
Terming the bill as a "draconian law", the Left parties said if the Punjab government did not withdraw it, they will launch a mass struggle, including a 'jail bharo' agitation.
While addressing the rally, Left leaders lashed out at the Punjab government and the Narendra Modi government.
Even a scheme benefiting the poor like MNREGA is being diluted and new labour laws are being introduced, affecting the security of the workers, he alleged.
Karat said such rallies would be held in other parts of the country also.
"Now our aim is to strengthen the Left," he said.
The rally was also addressed by veteran CPI leader A B Bardhan and CPI (ML) General Secretary Dipanker Bhattacharya.
