Environment Minister Shinjiro Koizumi said Monday he took 12 days of paternity leave over the course of one month after his son was born in January.
Koizumi has said he planned to take about 14 days of child care leave over three months and that he is considering extending it.
The Lower House member garnered attention last month when he said he would take paternity leave after the birth of his first child, a rare move in a country where only 6.16 percent of working fathers took such leave in fiscal 2018, compared with 82.2 percent of working mothers, according to government data.
He first mentioned his plan last August after he announced his marriage to his wife, TV personality Christel Takigawa.
"You become aware and learn about a range of things" by taking paternity leave, Koizumi told a gathering of ministry employees, including those considering taking the leave.
The government hopes to raise the rate of working fathers taking child care leave in the public and private sectors this year, and plans to encourage male civil service workers who qualify to take child care leave for a minimum of one month starting in April.