please follow below steps
1. Create Report 1 , this is your main report.
2. Create Report 2 , this will act as subreport.
3. Now open report 1 and from toolbox drag the subreport control to this main report.
4. Then Right click on the subreport control and configure it to Point to the Report 2.
5. Configure the Parameter For subreport , if you have to pass any paramter.
For more detail visit the following links:
http://shahfaisalmuhammed.blogspot.com/2011/10/building-subreport-in-reporting.html[
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http://forums.asp.net/post/3464322.aspx[
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