We report the discovery of Qatar-3b, Qatar-4b, and Qatar-5b, three new transiting planets identified by the Qatar Exoplanet Survey. The three planets belong to the hot Jupiter family, with orbital periods of P_Q3b=2.50792 days, P_Q4b=1.80539 days, and P_Q5b=2.87923 days. Follow-up spectroscopic observations reveal the masses of the planets to be M_Q3b=4.31±0.47 M_J, M_Q4b=6.10±0.54 M_J, and M_Q5b=4.32±0.18 M_J, while model fits to the transit light curves yield radii of R_Q3b=1.096±0.14 R_J, R_Q4b=1.135±0.11 R_J, and R_Q5b= 1.107±0.064 R_J. The host stars are low-mass main sequence stars with masses and radii M_Q3= 1.145±0.064 Ṁ, M_Q4=0.896±0.048Ṁ, M_Q5=1.128±0.056 Ṁ and R_Q3=1.272±0.14 RṀ, R_Q4=0.849±0.063 R , and R_Q5=1.076±0.051 Ṙ for Qatar-3, 4, and 5 respectively. The V magnitudes of the three host stars are V_Q3=12.88, V_Q4=13.60, and V_Q5=12.82. All three new planets can be classified as heavy hot Jupiters (M > 4 M_J).