中文摘要：

以1996--2007年间沪深两市的制造业企业为样本，通过配对样本T检验，比较了实施ERP企业在实施ERP前后的效率变化。进一步运用配对样本T检验和Tobit回归分析比较了实施ERP企业与未实施ERP企业的效率差异。研究结果表明：（1）对已实施ERP的企业而言，ERP实施中和实施后的效率与ERP实施前相比明显下降。（2）已实施ERP的企业和未实施ERP企业相比，实施ERP企业的效率明显高于未实施ERP的企业效率。（3）ERP实施对企业效率的影响因规模和财务健康状况的不同而存在差异。大规模企业效率改善的程度与ERP上线时间有关；ERP对财务状况健康的企业效率提高的程度稍高于不健康的企业，

英文摘要：

Using listed manufacturing companies from Shanghai and Shenzhen Stock Exchange between 1996 and 2007 as samples, this paper studies the change of efficiency after ERP implementation for the adopted ERP compa- nies by the pair T test. Furthermore, we compare the efficiency after ERP implementation for the adopted ERP firms with paired firms that had not adopted ERP systems through the pair T test and Tobit regression method. We draw conclusions as follows：l）The efficiency has been significantly declined the adopted ERP companies.2）Comparing the adopted ERP companies and during non-ad and after ERP implementation for opted ERP firms, the efficiency of the adopted ERP companies is much higher than the non-adopted ERP firms.3）The impacts of ERP implementation on the efficiency vary due to size and financial health of company. Bigger companies improve efficiency related to the ERP service time.ERP improves efficiency for health companies more obviously than unhealthy companies.