MIL-101(Fe) was investigated as a cathode material of lithium ion batteries. A battery test reveals that MIL-101(Fe) shows a charge and discharge capacitance of 110 mA h g⁻¹. It also showed reversible charge and discharge cycles and uptake of 0.62 Li/Fe after 100 cycles, which is the highest loading amount ever reported for the carboxylic MOFs. It also operates in the temperature range up to 350 °C and showed a good high thermal stability.