Your question isn't really clear. My guess is that you are asking if you should pursue the "Oracle Database 10g Administrator Certified Professional" or "Oracle Database 11g Administrator Certified Professional" certifications.
In general, I always recommend pursuing the most recent certification unless you have a good reason why the older one is a better fit for you. If you are currently working for a company that is using Oracle 10G, then it might make sense to pursue the 10G certification. An added benefit of that is the ability to then take the 11G upgrade test, at which point you will be certified in both 10G and 11G.