US Central Command says the strikes killed a total of 15 members of al-Qaida in the Arabian Peninsula. The four strikes were not previously announced.
Altogether, the US has launched nine strikes this year against the group, which the US says is a persistent threat in the region and to Western interests.
The Pentagon has been increasing its military support for operations against AQAP militants in Yemen, including intelligence, ships and special operations forces.
Al-Qaida had gained ground amid the chaos in Yemen.