Catalytic conversion of glycerol with iron oxide-based catalysts was investigated for the production of useful chemicals. The catalytic reaction was carried out in a fixed-bed flow reactor at 623 K under atmospheric pressure. Useful chemicals such as allyl-alcohol, propylene and ketones were produced from glycerol through two main pathways: formation of allyl alcohol and propylene (Pathway I), and formation of hydroxyacetone and acrolein (Pathway II). Hydroxyacetone in Pathway II is easily converted into carboxylic acids followed by ketonization to form acetone, methyl ethyl ketone and pentanone. An increase in the W/F (weight ratio of catalyst to feedstock) value allowed the consecutive reactions to progress and the final products were 24 mol%-carbon of propylene and 25 mol%-carbon of ketones. Moreover, addition of alkaline metals to the catalyst increased the yield of allyl alcohol. This study demonstrates the production of useful chemicals from glycerol (crude glycerol and reagent glycerol). The effects of catalyst composition and experimental conditions on these yields are discussed, based on investigations of the reaction pathways and mechanisms.