Trudeau, speaking to the Indian community in Canada, said this week that he was concerned about the farmers, most of them from the Sikh-dominated state of Punjab, camped out on the outskirts of Delhi in a protest against farm reforms.
The Indian foreign ministry said in a statement that comments on "issues relating to Indian farmers constitute an unacceptable interference in our internal affairs."
India and Canada have warm ties, but in recent years there has been concern in India that some Sikh leaders in Canada have ties to separatist groups hostile to India.
Canada is home to an influential Sikh community and Indian leaders say there are some fringe groups there that are still sympathetic to the cause of an independent Sikh state called Khalistan, carved out of India.
The Indian foreign ministry said comments made by Trudeau and other leaders had emboldened radical groups and they were a risk to its diplomatic staff based in Canada.
"We expect the Canadian Government to ensure the fullest security of Indian diplomatic personnel and its political leaders to refrain from pronouncements that legitimize extremist activism," it said.
There was no comment from the Canadian embassy.
The Indian government has held talks with the farmers to end the impasse and persuade them that farm reforms were in their interest in the long-term.
(Reporting by Sanjeev Miglani; Editing by Raju Gopalakrishnan)
By Sanjeev Miglani
