A fiber optic displacement sensor (FODS) using a transmission technique was developed to detect sugar contents in honey. This was achieved by measuring the output signal of non- and adulterated honey with different addition percentage volumes of sugar (fructose and glucose). Five types of honey samples were adulterated with different percentages of fructose and glucose ranging from 0% to 10%. Blue diode laser at 435 nm was used as a light source in this FODS. The performance of sensor showed that the voltage signal linearly increased with the concentration of adulteration of sugar. In contrast, the refractive index of the adulterated honey is found decreasing with the concentration of sugar. This means the higher sugar contents in adulterated honey the lower is the refractive index leading to high transmission in FODS. Thus, FODS based on a transmission technique has a potential to detect the sugar content in adulterated honey. The simplicity, faster, and cost effective made FODS as a promising technique for food industry.