Mycoplasma hominis is a widely spread mycoplasma (class Mollicutes), associated with socially important human diseases and contamination of cell cultures. Controlling infections caused by M. hominis depends on determining the molecular mechanisms responsible for the bacterium's survival in unfavorable conditions. A proteome analysis employing 2-DIGE and MALDI TOF/TOF MS was applied to identify, for the first time, 53 proteins of M. hominis PG37 whose levels altered in bacteria cultivated in stress conditions (starvation and low temperature). According to the protein classification by functional category (clusters of orthologous groups of proteins, COG), 47 of the 53 mycoplasma proteins identified are involved in fundamental cellular and biochemical processes: translation (12; 22.64%), transcription (2; 3.77%), posttranslational modification (7;13.20%), cell cycle control (2; 3.77%), energy production and conversion (6; 11.32%), carbohydrate transport and metabolism (3; 5.66%), amino acid transport and metabolism (8; 15.09%), nucleotide transport and metabolism (6; 11.32%), and inorganic ion transport and metabolism (1; 1.89%). For six proteins (11.32%), the function was not determined; 24 proteins (45.28%) were bacterial virulence factors. Those proteins of M.hominis PG37 whose expression is modulated in response to unfavorable environmental conditions are components of stress adaptation mechanisms in mycoplasma and potential targets for controlling infections caused by this bacterium.