The year 1646 in science and technology involved some significant events.

• Pascal's Law, a law of hydrostatics is developed, stating that, in a perfect fluid, the pressure exerted on it anywhere is transmitted equally.

• Dr Thomas Browne's Pseudodoxia Epidemica is published in London,^[1] introducing the words electricity, medical, pathology, hallucination and computer to the English language and casting doubt on the theory of spontaneous generation.^[2]

• April 20 – Charles Plumier, French botanist (died 1704)
• July 1 – Gottfried Leibniz, German scientist and mathematician (died 1716)

• November 29 – Laurentius Paulinus Gothus, Swedish theologian and astronomer (born 1565)