We characterize the absolute magnitudes and colors of RR Lyrae stars in the globular cluster M5 in the ugriz filter system of the Dark Energy Camera ( DECam ) . We provide empirical Period-Luminosity ( P-L ) relationships in all 5 bands based on 47 RR Lyrae stars of the type ab and 14 stars of the type c. The P-L relationships were found to be better constrained for the fundamental mode RR Lyrae stars in the riz passbands , with dispersion of 0.03 , 0.02 and 0.02 magnitudes , respectively . The dispersion of the color at minimum light was found to be small , supporting the use of this parameter as a means to obtain accurate interstellar extinctions along the line of sight up to the distance of the RR Lyrae star . We found a trend of color at minimum light with pulsational period that , if taken into account , brings the dispersion in color at minimum light to \leq 0.016 magnitudes for the ( r - i ) , ( i - z ) , and ( r - z ) colors . These calibrations will be very useful for using RR Lyrae stars from DECam observations as both standard candles for distance determinations and color standards for reddening measurements .