Japan says it plans to catch 227 whales between July and December.
The fisheries ministry announced the six-month quota on Monday before ships left to resume commercial whaling for the first time in 31 years. The ministry says the ships will only operate in Japan's territorial waters and exclusive economic zones.
On Sunday, Japan withdrew from the International Whaling Commission.
The ministry says the planned catch is based on an IWC-approved method to maintain resources, even if hunting continues for a century.
Japan says it caught 637 whales for research over the entire year of 2018. The new six-month quota of 227 translates into an annual reduction.
The numbers are set at 150 Bryde's whales, 52 minke and 25 sei whales.
The fisheries ministry says it doesn't expect a major change in the amount of whale meat for consumption entering distribution channels as the relatively large Bryde's whale has the biggest quota.