Several studies have determined the potential of the Fe-based superconductor metal material and its industrial application. However, this study analyzes the effects of sintering time and cooling process on FeSe superconductors synthesized using the powder in a sealed tube technique. The research was carried out by mixing and grinding the conventional analytical powders of Fe (99.9% purity) and Se (99.9% purity) in the stoichiometry ratio of 1:1 for three hours. The mixed powder was sealed and pressed in SS 316L tube using a uniaxial pressure of 150 MPa. Furthermore, the sintering process was carried out for 2 and 6 hours at 800°C, using the air (fast) and furnace (slow) cooling processes. The samples were characterized to analyze their superconductivity properties using a scanning electron microscope (SEM), x-ray diffraction (XRD), as well as their electrical resistivity versus temperature measurement using cryogenic systems. XRD results showed that a significant phase of β-FeSe with tetragonal acts as a superconductor metal material. In addition, the prolonged sintering time and cooling process led to the formation of amorphous hexagonal δ-FeSe. Therefore, based on the measurement of electrical resistance and temperature analysis, the optimum sample was obtained on a FeSe-1 with 2 hours sintering time and fast cooling in the air showing a sharp superconducting transition with Tc onset of 16 K and Tc zero of 7.75 K, respectively.