When cytosol ( ancient Greek κύτος kytos, cell ' and Latin solvere, solutum solve ', ' resolve '), also known as the cytosol, the liquid components of the cytoplasm of eukaryotic and prokaryotic cells are called.

The cytosol, there is about 70 % water, as well as the dissolved ions, small molecules and large water-soluble molecules, such as proteins. The protein content of the cytosol is 20-30 %. Depending on the cell type, 25-50 % of the total amount of protein found in the cytosol. In the cytosol is a part of the protein, rather than translation. Also, here many steps of protein degradation as well as many reactions of intermediary metabolism of the cell, see the glycolysis instead. These include synthesis and degradation of nucleotides or amino acids.

The cytosol is traversed in eukaryotes by a network of filamentary structures ( filaments) as actin filaments, intermediate filaments and microtubules that form the cytoskeleton ( cytoskeleton ) in its entirety.

In prokaryotes, the DNA is freely present in the cytosol, since they have no compartmentalization. Due to the heavy accumulation of macromolecules into the cytosolic aqueous salt solution is referred to in the cytosol of a gel rather than a true solution.