As part of the Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) we report the discovery of a pair of faint dwarf galaxies (CenA-MM-Dw1 and CenA-MM-Dw2) at a projected distance of $sim$90 kpc from the nearby elliptical galaxy NGC5128 (CenA). We measure a tip of the red giant branch distance to each dwarf, finding $D=3.63 pm 0.41$ Mpc for CenA-MM-Dw1 and $D=3.60 pm 0.41$ Mpc for CenA-MM-Dw2, both of which are consistent with the distance to NGC5128. A qualitative analysis of the color magnitude diagrams indicates stellar populations consisting of an old, metal-poor red giant branch ($gtrsim 12$ Gyr, [Fe/H]$sim-1.7$ to -1.9). In addition, CenA-MM-Dw1 seems to host an intermediate-age population as indicated by its candidate asymptotic giant branch stars. The derived luminosities ($M_V=-10.9pm0.3$ for CenA-MM-Dw1 and $-8.4pm0.6$ for CenA-MM-Dw2) and half-light radii ($r_{h}=1.4pm0.04$ kpc for CenA-MM-Dw1 and $0.36pm0.08$ kpc for CenA-MM-Dw2) are consistent with those of Local Group dwarfs. CenA-MM-Dw1s low central surface brightness ($mu_{V,0}=27.3pm0.1$ mag/arcsec$^2$) places it among the faintest and most extended M31 satellites. Most intriguingly, CenA-MM-Dw1 and CenA-MM-Dw2 have a projected separation of only 3 arcmin ($sim3$ kpc): we are possibly observing the first, faint satellite of a satellite in an external group of galaxies.
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