Co-pyrolysis of slop oil with ferrocene was carried out to convert waste of petroleum into carbon nanoparticles (CNPs). Since slop oil is a mixture of hydrocarbons (HCs) with broad molecular weight distribution, it could be simply fractionated into some certain fractions by batch distillation. Distillate containing hydrocarbons with small molecules was mainly focused as an alternative carbon source for synthesis of CNPs. A two-stage furnace was employed for evaporating a mixture of distillated slop oil and ferrocene at 200 °C in the 1st stage of the furnace and then formation of CNPs at 900 °C could be observed in the 2nd stage. Laboratory-grade ferrocene was mixed with slop oil with a designated weight-ratio of 1:2. Microscopic analyses based on SEM and TEM micrographs reveals that CNPs obtained from distillated slop oil mostly consist of bundles of multi-walled carbon nanotubes (MWCNTs) with nominal diameters of 20-50 nm. Raman spectroscopic analyses of the synthesized CNPs exhibit the notably high value of IG/ID, suggesting that the synthesized CNPs preferably consist of graphitic nanostructure. Moreover, TGA analysis shows that 39.8 and 32.9 wt% of Fe contents exist in the CNP samples synthesized from original slop oil and distillated slop oil, respectively.