Background: Tenofovir (TDF) is one of the recommended antiretrovirals that works by disrupting HIV DNA synthesis through competitive inhibition of Reverse Transcriptase and incorporation into the virus DNA. One of the side effects of TDF is kidney toxicity. Methods: This study is an analytical study with a cross-sectional design. Data were extracted from medical records to assess the long-term relationship of Tenofovir use with kidney function in pediatric HIV-infected patients at H. Adam Malik Central General Hospital (RSUP) in Medan. Data were statistically analyzed using independent t-test with SPSS software, with a significance level of p <0.05. Results: No significant differences were found in glomerular filtration rate with Tenofovir use < 1 year or > 1 year (p = 0.812), between asymptomatic and symptomatic HIV stages (p = 0.687), and between groups without immunodeficiency and those with immunodeficiency (p = 0.877). Conclusion: There is no relationship between the duration of Tenofovir use and kidney function impairment in pediatric HIV-infected patients at H. Adam Malik Central General Hospital in Medan.