Some 16,000 migrants arrived in April, down almost a quarter from 20,000 in March, and nearly a 90-percent plunge from December when 120,000 arrivals were recorded.
Syrians made up the biggest group of newcomers, with 2,724 applicants in the month. Afghans were the second largest group with 2,063 migrants, followed by Iraqis with 1,853 arrivals.
Germany last year took in more than one million refugees and migrants, with the flow accelerating after Chancellor Angela Merkel in September suspended normal EU asylum rules to grant safe haven to people fleeing the Syrian war.
The mass influx sparked a backlash in Germany - which has since reintroduced temporary border controls and taken other steps to reduce numbers - and in eastern Europe, where a string of Balkan countries in early March shut their borders to refugees flocking in from Greece.
The EU has also since agreed on a controversial pact with Turkey to stop refugees crossing by boat to Greece.
Under the deal, Turkey has agreed to take back migrants who arrived in Greece after March 20.
In return, Europe has pledged that for every Syrian deported, it will accept one refugee from Turkey's vast camps, a move it hopes will discourage people from taking the highly risky journey across the Aegean sea.