Entomology, the scientific study of insects and closely related terrestrial arthropods, has been impelled by the necessity of societies to protect themselves from insect-borne diseases, crop losses to pest insects, and insect-related discomfort, as well as by people's natural curiosity. This timeline article traces the history of entomology.

Entomology, the study of insects, progressed between 1800 and 1850, with the publication of important texts, definition of new orders such as Aphaniptera and Strepsiptera, and the shift to specialization. The following timeline indicates significant events in entomology in this time period.