Robert Knowles

• Robert P. Knowles, American politician, member of the Wisconsin Senate
• Robert E. Knowles, American politician, member of the Florida House of Representatives.
• Robert Edward Knowles, Canadian writer and clergyman.
• Robert Knowles , British parasitologist
• Rob Knowles, Australian politician
• Captain Robert Knowles, a fictional character in Bernard Cornwell's Sharpe series
• Robert Knowles, see Timeline of entomology since 1900