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The outer region of the jovian system between ∼50 and 300 jo-vian radii from the planet is found to be the host of a previously unknown dust population. We used the data from the dust detec-tor aboard the Galileo spacecraft collected from December 1995 to April 2001 during Galileo’s numerous traverses of the outer jo-vian system. Analyzing the ion amplitudes, calibrated masses and speeds of grains, and impact directions, we found about 100 indivi-dual events fully compatible with impacts of grains moving around Jupiter in bound orbits. These grains have moderate eccentricities and a wide range of inclinations—from prograde to retrograde ones. The radial number density profile of the micrometer-sized dust is nearly flat between about 50 and 300 jovian radii. The absolute number density level (∼10 km−3 with a factor of 2 or 3 uncertainty) surpasses by an order of magnitude that of the interplanetary back-ground. We identify the sources of the bound grains with outer irregular satellites of Jupiter. Six outer tiny moons are orbiting the planet in prograde and fourteen in retrograde orbits. These moons are subject to continuous bombardment by interplanetary microme-teoroids. Hypervelocity impacts create ejecta, nearly all of which get injected into circumjovian space. Our analytic and numerical study of the ejecta dynamics shows that micrometer-sized particles from both satellite families, although strongly perturbed by solar tidal gravity and radiation pressure, would stay in bound orbits for hun-dreds of thousands of years as do a fraction of smaller grains, several tenths of a micrometer in radius, ejected from the prograde moons. Different-sized ejecta remain confined to spheroidal clouds embrac-ing the orbits of the parent moons, with appreciable asymmetrie