The arrests were made in August as part of the 'Safety Pin Campaign', the Kathmandu Metropolitan Police Circle said.
They said they had deployed officials in plainclothes on public vehicles to discourage harassment of women travellers.
The police said 47 of the 70 men arrested during the campaign face criminal charges for insulting women in a public place. The remaining suspects were released with warning.
The suspects are aged between 18 and 30 years.
This was the first operation of this kind in Kathmandu, they added.