The appearance of a new threat to humanity – nanothreat – is connected to the epoch of discoveries in the field of physics and chemistry at the end of the last century: 1) By the creation of electronic microscopes capable to identify individual molecules and nanodimensional objects such as nanoparticles (nanophases) and nanostructures; 2) By detection of a new state of substance, the properties of which radically differ from all previously known. These substances are extremely chemically active and their influence on living organisms is largely not known yet. Nanoparticles from the environment, food and clothes can easily penetrate human organism by all accessible routes (nose, mouth and skin) and weaken (or injure) various organs. Therefore the nanoecological threat is practically uncontrollable. 3) By the appearance of an opportunity to manipulate separate molecules, by atoms and nanoparticles, and to create nanorobots, various optical and electronic nanosystems (which can be capable of self-reproduction). However, the process of self-reproduction of “smart” nanosystems potentially resulting with “grey goo” can be uncontrollable. Nanotechnological threat is connected to the creation of nanoweapons as well as nanosystems for the replacement of natural organs, potentially transforming Homo sapiens into nanopeople. Nanoprogress is created (as a rule) simultaneously with the development and deepening of democracy, therefore personal nanosensors of residence, intelligence and feelings will present the main threats at the nanodemocracy epoch.