Christopher Sandius Jr. (Königsberg, October 12, 1644 – Amsterdam, November 30, 1680) was an Arian writer and publisher of Socinian works without himself being a Socinian.
His name was Latinized as Christophorus Sandius, though his German name appears to have been Christoph Sand, and he was known as Christof Van den Sand during his later years in the Netherlands.
Following research by Lech Szczucki it appears that Sandius Jr. was well educated by his rigorous father, Christopher Sandius Sr., (d.1686) a government official in Königsberg, who himself was later removed from his office for anti-Trinitarian sympathies. Sandius Jr. moved to Amsterdam and earned his living as an editor, translator and publisher, he became well-recognized among European intellectuals. Sandius Jr. promoted the view that Arianism was the high point of the theology of the Early Church. He remained on good terms with exiled Polish Socinians Andrzej Wiszowaty and Stanislaw Lubieniecki, while engaging in friendly polemics with them on the problem of the pre-existence of Christ which they denied, but Sandius, as an Arian, accepted.