RATIONALE: The cigars have characteristic flavors in smoke when compared with cigarettes, and cigars from various origins also have a difference in taste. However, little information can be found about the difference in chemical components of smokes between cigar and cigarette as well as between cigars, so it is interesting to compare their pyrolysis product distribution. METHODS: The cigarette and cigar leaves were pyrolyzed in a microfluidized-bed reactor, and the pyrolysis vapors were condensed and collected using cold traps. Mass spectrometric analysis of condensed liquids was performed utilizing electrospray ionization-orbitrap mass spectrometry in both positive and negative ion modes. RESULTS: The mass spectra of condensable pyrolysis products of three tobacco leaves were obtained by Orbitrap-MS in both positive and negative ESI modes. The DBE values (to carbon atom number) and the relative distribution (to nitrogen or oxygen atom number) of different products were carefully compared and discussed. CONCLUSION: The main difference in pyrolysis products between cigarette and cigar leaves relates to N