Part-filter analysis method was used to estimate Chinese smokers' mouth level exposure (MLE) to nine chemical components in cigarette smoke. 1) A series of quantitative analysis methods for determining levels of nicotine, tar, solanesol and six harmful components (i.e. ammonia, crotonaldehyde, hydrogen cyanide, phenol, NNK and benzo[a]pyrene) in smoked cigarette filters was developed. The precision and recovery of the developed methods were satisfied for both whole-filter and part-filter. 2) According to the results of Chinese smokers’ smoking behaviours investigation and relevant literature, six smoking regimes were designed to estimate Chinese smokers’ MLE to cigarette smoke. Under the designed smoking regimes, the deliveries in mainstream cigarette smoke and retention by filter of the above nine target analytes were determined by taking cigarettes with different type filters (i.e. cellulose acetate filter, activated carbon filter, polypropylene fibre filter and paper filter) as samples. The linear regression equations of retention by whole-filter or part-filter versus the deliveries in mainstream cigarette smoke for the nine analytes were established, the correlation between linear regression equations for whole-filter method and part-filter method was investigated, and then part-filter analysis method was determined as the method used for estimating smokers’ MLE to the nine components. 3) A total of 123 Chinese male smokers were recruited and divided into three groups, each group smoked one of the three cigarettes with labelled ISO tar values of 6, 8 and 12 mg. The smokers’ MLE to the nine components was estimated with the developed part-filter analysis method. The results showed that the smokers’ mean MLE to smoke of cigarette with labelled ISO tar value of 6 mg was lower than that of 8 or 12 mg.