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In current Chinese timber structure design codes, due to lack of a determination method, design strength value of domestic dimension lumber can only be determined with reference to the design method of sawn and log timber structure, which is dependent only upon wood species and is not related to visual grade and size of dimension lumber. For rational determination of the design strength value of domestic dimension lumber, full scale tests for bending strength were conducted on different visual grades (grade Ic, IIc, IIIc, IVc) of Chinese larch dimension lumber, and then reliability analysis on bending strength of domestic dimension lumber was carried out by the first order second moment method. In order to predict accurately the tail of probability distribution of bending strength, this paper has suggested that the mean value and standard deviation could be determined with the truncated 25% tested data of bending strength. The statistical mean vaule and coefficient of variation of geometry size of Chinese larch dimension lumber should be modified and be equal to 1.00 and 0.05, respectively. Based on reliability analysis results, relationships between reliability index and partial factor for different visual grades dimension lumber under different fitting data, probability distribution models of bending strength, load combinations, and load ratios were investigated. Finally, according to the target reliability requirements specified in the GB 50068—2001 ‘Unified standard for reliability design of building structures’, the partial factors for resistance and the corresponding design values of bending strength for Chinese larch dimension lumber were given. [ABSTRACT FROM AUTHOR]