Comet Denning, or Denning's Comet, may refer to any of the three comets discovered by British astronomer, William Frederick Denning, below: 489P/Denning C/1890 O2 (Denning) C/1892 F1 (Denning)
It may also be a partial reference to several comets he co-discovered with other astronomers: 72P/Denning–Fujikawa C/1891 F1 (Barnard–Denning)