His earlier works include Philip per brief (1890); Untersuchungen über neutest. Schriften in the Protest. Jahrb. theolog. Studien und Schriftkommentar (1895-1897); Und was Luth. evangel. Kirche? (3rd. ed. 1890); Reisebriefe aus Palestina (2nd ed, 1901); Palestina und seine Gesch. (2nd ed. 1904); Die wichtigsten Fragen im Leben Jesu (1904); Urchristliche Literaturgesch (1904). His most important book is Die Schriften des neuen Testaments, in ihrer ältesten erreichbaren Textgestalt hergestellt auf Grund ihrer Textgeschichte (Berlin, Bd. I., 1902-1910); certainly the most important work on the text of the New Testament which had been published since Westcott and Hort's New Testament in the original Greek.
Von Soden introduced, besides a new notation of manuscripts, a new theory of textual history. He believed that in the 4th century there were in existence three recensions of the text, which he distinguished as K, H and I.
His descendant Wolfram von Soden was a noted Assyriologist.