The World Boxing Association (WBA) super featherweight champion Takashi Uchiyama and super flyweight champion Kohei Kono will defend their titles in May, their gym said on Monday.
The two bouts will take place in Tokyo on May 6.
It will be Uchiyama's seventh defence of the title he wrested from Juan Carlos Salgado of Mexico in January 2010.
Uchiyama, unbeaten at 19 wins, including 16 KOs and one draw, will take on 10th-ranked Jaider Parra of Venezuela.
Kono will fight against interim champion Liborio Solis of Venezuela, ranked top in the WBA, in his first defence after a knockout victory over then title-holder Tepparith Kokietgym of Thailand in December last year.
Kono has a record of 21 wins, including 13 KOs, against three defeats.