The purpose of the study is to compare the Prison Reform of 1879 carried out in Russia with the requirements of the Standard Minimum Rules for the Treatment of Prisoners adopted by the United Nations in 1955. The study was conducted on the example of the Tobolsk prison complex of the late XIX – early XX centuries, based on practically achieved results. The sources of the study were the materials of the State Archives of the Tyumen, Omsk, Tomsk regions, as well as the State Archives of the Russian Federation. The methodological basis of the study combines two approaches: modernization and civilizational, using two methods: comparative historical and actualization. The scientific novelty of the work lies in a new look at the Prison Reform of 1879 through modern European standards of the rights of prisoners. The results of the Prison Reform of 1879 were compared with the requirements of the UN on the following grounds: prohibition of discrimination, protection of religious rights, compilation of a register of prisoners, their breakdown into categories, sanitary conditions and nutrition, education, libraries, recreation, work and work of prison inspections. The comparison showed that at the turn of the XIX – XX centuries, the Tobolsk prison complex (“Prison Castle”) was an advanced penitentiary institution of that time, not only generally conforming to European standards of the mid-XX century, but partly surpassing them. The Russian government planned to extend the achieved experience to other places of detention, but the process was interrupted by the revolution of 1905-1907. The results of the study showed that in Russia, the humanization of imprisonment was based not only on the principles of utility and rationalism, but in many respects – on Orthodox ideas of mercy, therefore, initially coincided with future European standards. Meanwhile, some reform measures turned out to be premature, as they were carried out in conditions of exceptional poverty of the rest of the Russian people and the absence of the concept of “human rights” in their lives. This contradiction became one of the links in the system of socio-economic problems that eventually led Russia to revolution.