The suspected mafioso are believed to be involved in cocaine trafficking, money laundering, violence and bribery, said Eurojust, the European Union agency that coordinates cross-border crime fighting.
Police swooped on locations in Italy, Germany, the Netherlands and Belgium in a series of co-ordinated raids.
While the Sicilian Mafia was made famous in films and television, 'Ndrangheta is thought to control as much as 80 percent of Europe's cocaine trade, and with some 6,000 members, is a substantial and far-spread force in European crime. Cocaine and ecstasy pills also were seized in the raids.
Eurojust said those detained are suspected of drug trafficking, money laundering, bribery, and violence.
"It's nearly a cliche, but the operation carried out today confirms again the great danger of the 'ndrangheta, not just in drug trafficking, where it's the undisputed leader, but (also) in the financial sphere", said Francesco Ratta, a top police official in the southern Italian region of Calabria.
The group has links with drug cartels in Colombia and Mexico, Italian anti-Mafia prosecutor Federico Cafiero de Raho said in The Hague.
In Germany, federal police said there had been multiple arrests in the early morning raids.
Officials hailed Wednesday's operation as a serious blow to the group.
Some 2 million euros (2.3 million dollars) in criminal assets was seized, Eurojust Vice-President Filippo Spiezia said in The Hague.
"We send a clear message to organised crime groups across Europe".
Prosecutor Fred Westerbeke said they had also probed ice cream parlours, adding that together with restaurants "the suspicion is that the mafia organisation is laundering money through these establishments and they are used as a cover for their criminal organisations".
The 'ndrangheta "is the most important organized crime group in the world", said Gen. Alessandro Barbera, who commands the investigative unit of Italy's financial police corps.
Dutch outlet NOS said that the 'Ndrangheta is known to operate its drug smuggling through the country's vibrant flower-trading industry.
The European police agency Europol said it was a "decisive hit against one of the most powerful Italian criminal networks in the world".
Wednesday's raids come a day after the new suspected head of the Cosa Nostra and 45 other alleged gangsters were arrested.
Jeweller Mineo, 80, was detained along with at least 45 others just before he was due to be appointed official heir to notorious mafia boss Toto Riina who died in prison a year ago.