Solomon Ayllon (c. 1655 or c. 1660 – 10 April 1728) was Haham of the Sephardic congregations in London and Amsterdam, and a follower of Shabbethai Ẓebi. His name is derived from the town of Ayllon, in what is now the province of Segovia.

Ayllon was neither a general scholar nor a Talmudist of standing, but his history is closely interwoven with that of Sabbateanism (Sabbatai Zevi, Nathan of Gaza and Nehemiah Hayyun) in both the East and the West.

Ayllon's youth was spent in Salonica, which was probably his birthplace, although some say that Safed was the place, however, many Sabbateans claimed to be of Palestinian birth. He associated with the Sabbatean circles of Joseph Philosoph, Solomon Florentin, and other leading spirits of antinomian and communistic tendencies. There he is said to have married as his divinely appointed spouse a woman from whom another man had separated without the formality of a divorce, only to experience that she soon left him for a third spouse, whose "affinity" seemed holier to this strange sect than the bonds of lawful matrimony.

In 1687 his daughter Gratia was born in Jerusalem. One year later, he visited Europe as a meshullaḥ (messenger) from the Palestinian congregations to collect funds for the poor of Palestine, leaving his wife and children domiciled in Safed, and having apparently publicly broken with Sabbateanism. From Livorno, where he was in 1688, he repaired to Amsterdam and thence to London, where, after a few months' stay, he was appointed haham on 6 June 1689.

The next year, however, he was vigorously attacked by a member of the congregation, named Jacob Fidanque, who had heard something of Ayllon's antecedents. The Ma'amad, caring more for its dignity than for the truth, endeavoured to suppress the scandal, but Ayllon's position was so hopelessly undermined by the exposure, that all the really learned members of the congregation would not submit to the new haham, which caused considerable friction, in spite of a pronunciamento ("haskamah") issued by the Ma'amad that under penalty of excommunication it was forbidden "to any one except the appointed haham to lay down the law or to render any legal decision".

Ayllon, in a letter to Sasportas six years later (1696), still complained bitterly of the unbearable relations between him and his congregation, and inasmuch as his Sabbatean proclivities began to reassert themselves, and the congregation just then began to consider the propriety of asking for his resignation (M. Ḥagis, l.c.), he resolved to leave London, (Homerton Hackney?) and was glad to accept an appointment as associate rabbi of the Sephardic congregation of Amsterdam, 1701.

Ayllon's first blunders in his new home took place in 1700, when he pronounced harmless a heretical work by Miguel Cardoso (probably the work "Boḳer Abraham," still extant in manuscript), which he had been requested to examine by the Ma'amad.

This latter body, however, was somewhat distrustful of its ḥakam, and sought additional opinions from other learned authorities. They gave their opinion that Cardozo's work merited public burning, and this sentence was actually carried out.