A catalyst composition that is especially useful in the hydroconversion of pitch, micro carbon residue and sulfur contents of a heavy hydrocarbon feedstock without the excessive formation of sediment. The catalyst composition is a reasonably high surface area composition containing alumina and a low molybdenum content with a high ratio of nickel-to-molybdenum. The catalyst composition further has a unique pore distribution that in combination with the special metals loading provide for good conversion of pitch and micro carbon residue without an excessive yield of sediment.