Human Immunodeficiency Virus (HIV) is an infection that attacks immune system. It's known as CD4 cells. The decreasing of CD4 cells will increase risk of having opportunistic infection (OI), then leads to AIDS. The aim of this research was to know the correlation between CD4 count and opportunistic infection on patients who infected to HIV/AIDS in RSUD Arifin Achmad Provinsi Riau period of 2015…