Purpose:This study aims to discuss the strategies for mapping from Dewey Decimal Classification(DDC)numbers to Chinese Library Classification(CLC)numbers based on co-occurrence mapping while minimizing manual intervention.Design/methodology/approach:Several statistical tables were created based on frequency counts of the mapping relations with samples of USMARC records,which contain both DDC and CLC numbers.A manual table was created through direct mapping.In order to find reasonable mapping strategies,the mapping results were compared from three aspects including the sample size,the choice between one-to-one and one-to-multiple mapping relations,and the role of a manual mapping table.Findings:Larger sample size provides more DDC numbers in the mapping table.The statistical table including one-to-multiple DDC-CLC relations provides a higher ratio of correct matches than that including only one-to-one relations.The manual mapping table cannot produce a better result than the statistical tables.Therefore,we should make full use of statistical mapping tables and avoid the time-consuming manual mapping as much as possible.Research limitations:All the sample sizes were small.We did not consider DDC editions in our study.One-to-multiple DDC-CLC relations in the records were collected in the mapping table,but how to select one appropriate CLC number in the matching process needs to be further studied.Practical implications:The ratio of correct matches based on the statistical mapping table came up to about 90%by CLC top-level classes and 76%by the second-level classes in our study.The statistical mapping table will be improved to realize the automatic classification of e-resources and shorten the cataloging cycle significantly.Originality/value:The mapping results were investigated from different aspects in order to find suitable mapping strategies from DDC to CLC while minimizing manual intervention.The findings have facilitated the establishment of DDC-CLC mapping system for practical applications. Purpose: This study aims to discuss the strategies for mapping from Dewey Decimal Classification (DDC) numbers to Chinese Library Classification (CLC) numbers based on co-occurrence mapping while minimizing manual intervention. Design / methodology / appach: Selective statistical tables were created based on frequency counts of the mapping relations with samples of USMARC records, which contain both DDC and CLC numbers. A manual table was created through direct mapping. In order to find reasonable mapping strategies, the mapping results were compared from three aspects including the sample size , the choice between one-to-one and one-to-multiple mapping relations, and the role of a manual mapping table. Findings: Larger sample size provides more DDC numbers in the mapping table. The statistical table including one-to-multiple DDC-CLC relations provides a higher ratio of correct matches than that including only one-to-one relations. The manual mapping table can not produce a better result than the statistical tables.Therefore, we should make full use of statistical mapping tables and avoid the time-consuming manual mapping as much as possible. Research limitations: All the sample sizes were small. We did not consider DDC editions in our study. One- multiple DDC-CLC relations in the records were collected in the mapping table, but how to select one appropriate CLC number in the matching process needs to be further studied.Practical implications: The ratio of correct matches based on the statistical mapping table came up to about 90% by CLC top-level classes and 76% by the second-level classes in our study. Statistical chart table will be improved to realize the automatic classification of e-resources and shorten the catalog cycle significantly. Originality / value: The mapping results were investigated from different aspects in order to find suitable mapping strategies from DDC to CLC while minimizing manual intervention. The findings have facilitated the establishment of DDC-CLC mapping systemfor practical applications.