Museveni, 79, who has led Uganda for 38 years, named 49-year-old son Muhoozi Kainerugaba as the East African country's new Chief of Defence Forces last week.
In a formal handover ceremony on Thursday, Kainerugaba "vowed to improve the welfare of soldiers by fighting the evil of corruption and mismanagement of resources", according to a statement released by the military.
Uganda's military plays a significant role in regional peace and has contingents deployed in Somalia and Democratic Republic of Congo where troops are helping battle Islamist insurgents.
Uganda's opposition has accused Museveni of fast-tracking his son's military career to prepare him to take political power. Museveni has denied grooming him for the presidency.
In 2022, Museveni removed Kainerugaba from his post as commander of Uganda's land forces after he made threats to invade neighbouring Kenya in posts on social media platform X.
Kainerugaba, who also praised Russian President Vladimir Putin after Russia's invasion of Ukraine, later said the threats were a joke.
(Reporting by Elias Biryabarema; editing by George Obulutsa and Mark Heinrich)
