There are several data set repositories. The most common are:

1) the UCI repository http://archive.ics.uci.edu/ml/

2) the KEEL repository http://sci2s.ugr.es/keel/datasets.php

3) FKI repository http://www.iam.unibe.ch/fki/databases

4) Kaggle https://www.kaggle.com (not a repository by itself but it has plenty of large problems).

There are several data set repositories. The most common are:

1) the UCI repository http://archive.ics.uci.edu/ml/

2) the KEEL repository http://sci2s.ugr.es/keel/datasets.php

3) FKI repository http://www.iam.unibe.ch/fki/databases

4) Kaggle https://www.kaggle.com (not a repository by itself but it has plenty of large problems).

Http://archive.ics.uci.edu/ml/datasets.html

Andreu and Chaurasia have given good websites for image datasets.

I hope these sites will help you a lot....

Have a good day!!!

please see the following ling for any type of data set you want . This site is UCI machine repository , I.e university of California.

http://archive.ics.uci.edu/ml/

Thank you very much for your kind support please.

If you need a database for iris recognition you should have a look at the following websites. You can also find databases for other biometric traits there.

http://biometrics.idealtest.org/

http://www3.nd.edu/~cvrl/CVRL/Data_Sets.html

For noisy color iris images, you can go to

http://iris.di.ubi.pt

Here you will get planty of Iris image datasets....

http://biometrics.idealtest.org/findTotalDbByMode.do?mode=Iris

dear sir 

see the following website its contain biometric database 

http://biometrics.idealtest.org/#