This work presents a study on the structural and magnetic properties of molybdenum trioxide (MoO3), both in its pure form and doped with iron (Fe), with the aim of expanding its industrial applications. The main goal is to enhance its magnetic properties through doping and the control of structural defects. The study is divided into three parts. In the first part, a structural and magnetic study of Fe-doped MoO3 was conducted. The material was produced by the solid-state reaction method, involving the thermal decomposition of ammonium molybdate and mixing it with different concentrations of Fe. The resulting samples were characterized by Raman, SEM, FTIR, and XRD, confirming the orthorhombic phase. The magnetic properties were analyzed using VSM, revealing an unusual behavior in the hysteresis curve. To further investigate this phenomenon, MoO3 was synthesized in a furnace, allowing precise control of environmental conditions, pressure, and temperature to regulate the material s structural defects. The second part of the study investigates the optimal environmental and temperature conditions for the formation of MoO3 with different structural defects while maintaining phase purity and preventing the formation of secondary phases. Syntheses were carried out in O2, H2, and Ar atmospheres at temperatures of 450, 550, and 650 degrees celsius, and the samples were characterized using the same techniques as before. The results showed that secondary phases formed in H2 and Ar atmospheres, while the material remained pure in the O2 environment throughout the process. Finally, in the third part, MoO3 was synthesized in an O2 atmosphere, with variations in time and temperature, to obtain samples with different levels of structural defects. The samples, synthesized using the same method as in the second part, were characterized by Raman spectroscopy, FTIR, XRD, and XPS, and their magnetic properties were studied using VSM. The results indicated that variations in the number of structural defects among the samples are directly related to their magnetic properties, which may explain the atypical behavior observed in this material.