The year 1603 in science and technology involved many events, some of which are listed below.

See also: 1602 in science, other events of 1603, 1604 in science, and the list of years in science.

Astronomy

• Johann Bayer publishes the star atlas Uranometria.

Exploration

• The first successful French colony in North America, Acadia, is founded.

General

• Accademia dei Lincei, the oldest scientific academy in the world, is founded in Rome

Medicine

• Girolamo Fabrici studies leg veins and notices that they have valves which only allow blood to flow toward the heart.

Births

• Abel Tasman, explorer

Deaths

• François Viète, mathematician.