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CO2 hydrogenation toward gaseous and liquid hydrocarbons has been experimentally studied over a Fe–K/Al2O3 catalyst in a fixed-bed reactor. At 15 bar, 300 °C, 2080 N mL/gcat/h, and H2/CO2 ratio of 3, the catalyst is able to convert CO2 to an extent of 30% and with a CO selectivity around 10%. Among hydrocarbons, linear short olefins C2–C4 are the most abundant product, but linear paraffins and alcohols are also formed and chains until 30 carbon atoms are detected. Operating parameters were varied (T between 250 and 300 °C, total pressure between 10 and 25 bar, H2/CO2 ratio between 3 and 24, and GHSV between 832 and 7059 N mL/gcat/h) in order to study their effects on the catalyst activity and selectivity. It was observed that the H2/CO2 inlet molar ratio is a very important parameter, and a large excess of H2 at the reactor inlet could lead to a significant increase of the CO2 conversion, with a minimization of the CO formation. Moreover, a semiempirical macrokinetic model for this reaction was developed. The model is able to describe with good accuracy the CO2 conversion and CO selectivity, as well as hydrocarbons distribution according to their C number and their chemical nature. The model is able to predict the experimental data within an error of 20% and with a MARR lower than 5% in the experimental domain considered.