Please go through the link to understand how to create datasets and populate date on to your reports
Working with Datasets
The steps to create a dataset which retrieves current date is
1.Create a new dataset .Go to the data tab of your report and click on the drop down menu and select < new Dataset >
- A dialog box will appear where u need to enter the SQL query
3.When u click ok ,you will see the newly created dataset in the dataset windows
4.You can execute the sql query just to verify whether you are getting the current date or not .
5.Then in the Layout panel drag a Textbox in the header and then drag the column from the newly created dataset into it or you can write an expression
=First(Fields!DD_MM_YYYY.Value, "GettingDate")
There is another way of getting the current date and time from SSRS itself instead of creating a dataset .You can use the inbuilt date and time functions in the SSRS .