His works are: Be'er Yizhak (1858; 19482); Nahal Yizhak (2 pts., 1872–84); Ein Yizhak (2 pts., 1889–95); Ez Peri (1881; 1903); Devar ha-Shemittah (1889). His letters have been printed in various collections. His works contain commentaries and novellae to the Shulhan Arukh, particularly responsa to questions submitted to him from the various Jewish communities in which he was regarded as the leading authority of his generation. R. Spektor exercised leniency, particularly in relieving the burden of many agunot. His 158 responsa on this subject reveal only three cases where he could not find a basis for permitting the woman to remarry. Many Torah institutions were named after him.