The aim of this paper is the gear design of a 100 Watts horizontal axis wind turbine (HAWT). This is for integration into a prototype HAWT as a starting point to facilitate improved electricity supply. The procedure involved the use of gear design principles, bending theory, applicable codes and standards to achieve the design and material selection, and the gears were modelled with AutoCAD. Based on the determined module of 2mm, the design results indicate a gear diameter of 26.6mm with 13.3 teeth on the output shaft coupled to the generator to deliver a rotational speed of 800 revolutions per minute (rpm) would mesh with a 28 teeth, 56mm diameter rotor shaft gear speed running at a speed of 381rpm. The gears face width and tooth thickness were also being found to be 20mm and 3.14mm respectively. Due to bearing boundary dimension standardization constraint, 17mm and 7mm were selected for the main and output gears internal diameters respectively which should correspond to shafts nominal diameters. Reduction in bending stress was found as pressure angle increased. The induced bending stress at pressure angle of 200 was 23.58N/mm2, a lower value compared to the design bending stresses for mild steel and A6061 respectively for the fillet stress concentration factors.