The effective atomic numbers (Zeff) and effective electron density (Ne) of chitin have been calculated using the mass attenuation coefficients (μ/ρ) obtained via XCOM (COMpilation of X-ray Cross Sections) in the photon energy range between 1 keV and 1 GeV. The results were compared with the measured values at the photon energy of 662, 1173 and 1332 keV. Both measured and calculated results were in good agreement. © 2011 Academic Journals.