The 13-km long stretch spans across Aluva and Palarivattom areas of the port city and will start operating from June 19.
PM Modi, took a brief ride in the metro prior to the official launch with dignitaries including Governor P Sathasivam, Chief Minister Pinarayi Vijayan, Union Urban Development Minister M Venkaiah Naidu and India's "Metro Man" E Sreedharan.
Modi, who cut the ribbon at the Palarivattom station, shook hands with Vijayan and Sreedharan before proceeding to board the metro train.
During the journey, the PM waved at the crowd as Sreedharan and Kochi Metro Rail Ltd Managing Director Elias George interacted with him.
He later tweeted that the metro had "several significant features, which make it a state-of-the-art project that will enhance Kochi’s economic growth."
Hailed as India's first integrated multi-mode transport system, the inaugural ceremony was held at Kochi's Jawaharlal Nehru International Stadium.
In his address, PM Modi stressed the need to bring about a "paradigm shift" in urban planning by adopting a people-centric approach and integrating land use and transport.
The prime minister, who began his speech in Malayalam, said he was happy to be part of the inauguration of the project. He said Kochi was selected as a Smart City in January 2016.
"I hope it will do even better in the days to come," he said.
Kochi, the queen of the Arabian Sea, was once an important spice trading centre. Today it is known as the commercial capital of Kerala, the prime minister said.
Kochi Metro Rail Limited (KMRL) is a 50-50 joint venture of the Centre and the state government.
The Centre has so far released over Rs 2,000 crore for the project. The coaches reflected 'Make in India' vision. They have been built by Alstom near Chennai and have an Indian component of around 70 per cent, he said.
The Kochi Metro Rail System has collaborated with Kudumbashree, the women empowerment self-help group initiated by the state government. It has also appointed as many as 23 transgenders for customer service operations and as ground staff.
Apart from a fleet of low-floor buses and autos plying as metro feeders, a water metro will soon join the Kochi Metro giving the city a multi-dimension mobility network, especially for people living in the backwaters.
The rooftops of all metro stations have been set up with solar panels in order to generate power.
A special provision for wheelchairs, special coaches for people with disabilities, multiple USB ports for charging mobile phones, and cushioned seats for the disabled and pregnant women are some key features of the metro.
The minimum fare has been capped at Rs 10, while an end-to-end ride, from Aluva and Palarivattom or vice-versa costs Rs 40.
Considered the fasted completed metro project in the country, the estimated cost of completion of the Kochi Metro is Rs 5,181.79 crore.
The 13-km long stretch spans across Aluva and Palarivattom areas of the port city ||Hailed as India's first integrated multi-mode transport system, the inaugural ceremony was held at Kochi's Jawaharlal Nehru International Stadium ||