Aging is a process of reversible and/or irreversible structural change of material, which depends on structural characteristics and environmental factors. Heat, humidity, UV radiation, chemical effects and their causes in visible and invisible damages which lead to structural deteriorations and decreases in fastness are some factors that depends on aging in leathers and leather products. In this research, Chromium (VI) and formaldehyde contents which resulted after artificial aging procedure in chrome, vegetable and semi-vegetable tanned garment leathers, caused by the chemical decomposition have been investigated. Temperature, temperature/humidity and temperature/UV radiation have been chosen as aging factors. According to the findings; in finished garment leather samples, Chromium (VI) and formaldehyde contents higher than acceptable limits and aging conditions effective on level of increase have been investigated through ISO 17228 (2005) artificial aging procedure depending on temperature, humidity and UV radiation.