London Jews Society (London Society for Promoting Christianity amongst the Jews) is an Anglican missonary society founded in 1809 in order to promote Christianity among the Jews. In the 19th century the society was active in the capital of the Ottoman Empire, Istanbul and established several facilites in various districts of the city. Among the schools they founded in Istanbul, the one which served longest was in the district called Haskoy, which became the centre of London Jews Society Istanbul Mission at the end of the 19th century Today on the site of this centre stands another school called Haskoy Elemantary School. In this work first the history of the society and the conversion of Jews in England will be examined. Subsequently it will be focused on the history of the society in Istanbul and Haskoy British school will be analysed in the light of architectural drawings found in the Ottoman Archive.