The standard methods for analysis of cigarette smoke are mostly offline measurements such as GC-MS. However, tobacco smoke is an extremely complex mixture of particles and vapours, containing thousands of compounds some of which are harmful and can undergo rapid changes in concentration. The application of on-line measurement methods such as time-of-flight mass spectrometry (TOFMS) combined with a soft ionisation technique is expedient to analyse such difficult mixtures. Single photon ionisation (SPI) is a soft ionisation technique with almost no fragmentation. Additionally, the energy of the vacuum ultraviolet (VUV)-photons generated by a laser (E = 10.49 eV) or by an argon (Ar)-excimer lamp (E = 9.8 eV) is insufficient to ionise matrix constituents such as nitrogen. Subsequent TOF-MS parameters allow the detection of organic compounds with a high time resolution. In this regard, a cigarette combustion simulator is used for pyrolysis of tobacco. The simulator is designed to incinerate/pyrolyse a sample in close approximation to the burning conditions experienced by a lit cigarette. It allows parameters such as smouldering and puff temperature as well as combustion rate and puffing volume to be varied and controlled. The objective of the study was to compare smoke chemical composition generated by the simulator and a real cigarette.The smoking simulator was coupled to the mass spectrometer by a specially designed adapter that enables the analysis of pyrolysis and combustion gases of tobacco and tobacco products (e.g. 3R4F reference cigarette) with almost no aging. The measurements are not influenced by dead volume or memory effects. This facilitates investigation of several toxicants' formation under different puffing conditions (e.g. based on ISO and Canadian intense regimes) and other parameters (e.g. change of puff and smouldering temperature, nitrogen atmosphere). The measurement enables distinction between the different smoking conditions on the basis of the corresponding mass spectra and the results of their statistical evaluations (e.g. Fisher value, principal component analysis). The formation of five selected substances are monitored in more detail: Nitrogen monoxide, Acetaldehyde, 1,3-Butadiene, Benzene and Phenol.