Background <p>Susceptibility to metabolic dysfunction-associated fatty liver diseases (MAFLD) shows a large inter-ethnic variability. Currently, large-scale genome-wide association studies (GWAS) on MAFLD in a Korean population are limited. This study aimed to investigate genes underlying MAFLD in a Korean population.</p> Methods <p>A total of 13,457 Korean adults (4061 cases and 9396 controls) who underwent abdominal ultrasonography, biochemical testing, and genetic studies at a comprehensive health promotion center from 2019 to 2023 were included. Genome-wide genotyping was conducted using Infinium Asian Screening Array and an iSCAN system (Illumina, San Diego, CA, USA). Gene-based approach was conducted with Multi-Marker Analysis for Genomic Annotation (MAGMA) and Functional Mapping and Annotation (FUMA). Expression quantitative trait loci (eQTLs) mapping was done using GTEx v8 data.</p> Results <p>The 22q13.3, 19p13.11, and 2p23.3 loci were associated with MAFLD after adjusting for age, sex, and body mass index (<i>p</i> &lt; 5 × 10^–8). Of these, 154 (89%) variants were identified as eQTLs (FDR &lt; 0.05). Gene-based approach showed that <i>PNPLA3</i>, <i>SAMM50</i>, and <i>PARVB</i> were significantly associated with MAFLD (Bonferroni-corrected <i>p</i> &lt; 2.99 × 10⁻⁶), followed by <i>PDLIM4</i>, <i>GCKR</i>, <i>APOB</i>, <i>GPAM</i>, <i>HMGA1</i>, <i>C5orf56</i>, and <i>APOC1</i>.</p> Conclusions <p>This is the largest-scale GWAS of MAFLD in a Korean adult population. Genotyping <i>PARVB</i> as well as <i>PNPLA3</i> might help us identify individuals with the highest risk of MAFLD in Korean adults. These findings would contribute to our understanding of genetic pathogenesis of MAFLD in the Korean population.</p>