Authorities say most of the people detained were found in bars, hours after the night-time curfew, that has been in place since March, came into force.
Kenya has registered more than 1,000 coronavirus-related deaths while 62,000 people have been infected.
The police have been conducting crackdowns on bars and entertainment spots across the country that have been ignoring the strict measures put in place to contain a second wave of the virus.
Over the weekend, hundreds of revellers were detained in various counties for failing to wear masks and for being in bars and pubs after the stipulated time of 21:00.
Police say all those arrested will appear in court and face a fine of up to $200 (£150).
Several bars found to have been operating after hours have now had their licences revoked and authorities say they will not be renewed.
The enforcement of the measures is among directives given by President Uhuru Kenyatta to try and stop the spread of coronavirus which has spiked in some rural communities in the country.