Navy patrol boat HMAS Glenelg intercepted the vessel north-west of Christmas Island today, AAP news agency reported.
"Initial indications suggest there are 164 passengers and six crew on board," Home Affairs Minister Jason Clare said in a statement.
The passengers will now be transferred to Christmas Island for security, health and identity checks, the report said.
The boat is the largest since February 2010, when a vessel with 185 people arrived in Australian waters.
Today's interception was the third this week and brings the total arrivals in April to 914 asylum-seekers and 29 crew.
It is the largest monthly asylum-seeker tally since August 2001, when 1645 passengers and crew sailed into Australian waters.
This year a total of 2173 asylum-seekers and 67 crew have arrived on 30 boats - almost double the arrivals over the same period last year.