The zirconium fumarate metal-organic framework (MOF-801) and mesoporous carbon (MC) composite was prepared by a conventional method. Compared with MOF-801, MOF-801/MC has a larger specific surface area, pore volume, improved conductivity, and better electrocatalytic performance. The new electrochemical sensor based on MOF-801/MC exhibits significant electrocatalytic activity for the oxidation of GA and the redox of luteolin. And the mechanisms of these two substances are discussed. Under the optimum test conditions, the detection of GA displays a wider linear range, consisted of two linear segments (0.2–5 and 5–100 μM) and the limit of detection (LOD) is 0.15 μM (S/N = 3). At the same time, the detection of luteolin also exhibits two linear relationships, 0.02–0.2 and 0.2–10 μM with LOD of 2.90 nM (S/N = 3). In addition, the MOF-801/MC sensor has good stability, selectivity and reproducibility. MOF-801/MC/GCE sensor was also used for detection of GA and luteolin in green tea and urine with satisfactory results.