This paper aimed to determine how the directivity was affected by the dielectric substrate in the dipole antenna. The researchers had to choose different substrates and specific property of antennas in order to produce this study. Given all these substrates, the study focused on which of these would produce the best results that would be beneficial to antennas of a certain function. For this case, it is the directivity of the antenna that is being researched on. Through the use of the Matrix Laboratory (MATLAB) software, the researchers were able to conduct a comparative study on these different substrates to obtain their directivities. After the researchers conducted the simulation, the dielectric substrate, Fused Quartz was found to have the least value in directivity while Air had the highest directivity. Additionally, the researchers were able to deduce that the lower the constant of the material, the higher the directivity of the material. This showed that the relationship between the two variables was inversely proportional.