Hu made the appointments in line with decisions made by the Standing Committee of the NPC, China's top legislature.
Huang Songfu was appointed ambassador to Portugal, replacing Zhang Beisan.
Song Yanbin was appointed ambassador to Costa Rica, replacing Li Changhua.
Qi Dayu was appointed ambassador to Kyrgyzstan, replacing Wang Kaiwen.
Li Yanduan was appointed ambassador to Samoa, replacing Zhao Weiping.