The use of inhibitors to control corrosion of metals and alloys, which are in contact with aggressive media, it is now generally accepted practice. A large number of organic compounds have been studied in order to test the effectiveness of their corrosion inhibition. Studies have shown that organic compounds, especially those with oxygen, nitrogen and sulfur, have a high efficiency in the process of protecting metals against corrosion. However, many of these compounds are expensive, but also very toxic to humans and the environment. Therefore, the current investigations are mostly directed towards studies of environmentally friendly inhibitors such as tannins, natural polymers and plant extracts. In this work the effect of temperature on the efficiency of corrosion protection of structural steel in acid medium by adding Aloe vera as ecological inhibitor. By the method of potentiodynamic polarization it was found that increasing the concentration of Aloe vera to 10% in the acidic medium reduces the corrosion rate and increases the inhibitor effectiveness. However, the effectiveness of Aloe vera as an inhibitor decreases with increasing the temperature. Analysis of electrochemical impedance spectroscopy revealed that with increasing concentration of Aloe vera to 10% increases charge transfer resistance, which means that the protective layer increases, which enables an increase of corrosion resistance. Metallographic investigations of structural steel microstructure after corrosion in acidic medium with different concentrations of Aloe vera have revealed white clusters of iron oxicarbides adsorbed on the metal surface, which originate from organic compounds of Aloe vera, and act as centers of corrosion protection.