  ATCA HI and radio continuum observations of the peculiar southern galaxy IC2554 and its surroundings reveal typical signatures of an interacting galaxy group. We detected a large HI cloud between IC2554 and the elliptical galaxy NGC3136B. The gas dynamics in IC2554 itself, which is sometimes described as a colliding pair, are surprisingly regular, whereas NGC3136B was not detected. The HI cloud, which emerges from IC2554 as a large arc-shaped plume, has a size of about 30 kpc, larger than that of IC2554. The total HI mass of the IC2554 system is about 2 x 10^9 Msun, a third of which resides in the HI cloud. It is possible that tidal interaction between IC2554 and NGC3136B caused this spectacular HI cloud, but the possibility of IC2554 being a merger remnant is also discussed. We also detected HI gas in the nearby galaxies ESO092-G009 and RKK1959 as well as an associated HI cloud, ATCA J1006-6710. Together they have an HI mass of about 4.6 x 10^8 Msun. Another new HI source, ATCA J1007-6659, with an HI mass of only about 2.2 x 10^7 Msun was detected roughly between IC2554 and ESO092-G009 and corresponds to a face-on low surface brightness dwarf galaxy. Star formation is evident only in the galaxy IC2554 with a rate of about 4 Msun/yr. 
ATCA HI Observations of the Peculiar Galaxy IC2554