This study revealed the proton density fat fraction (PDFF) of lumbar vertebral bone marrow in different age groups and gender of normal adults using iterative decomposition of water and fat with echo asymmetry and least squares estimation (IDEAL) technique. We demonstrated significant differences of lumbar vertebral bone marrow PDFF across three age groups. Particularly, the highest PDFF was found in the oldest group. We also found a moderate positive correlation between age and PDFF, while the correlation was higher in female than in male. Taken together, our findings pave the way for exploring age-related lumbar vertebral diseases and metabolic disorders.