I have a tattoo on my hand ,will be there any issue at the time of medical

Dear Vivek, we shall be honest with you. SSC CGL is not confined to one particular post. Various departments recruit candidates to their departments through SSC CGL. However, the Physical Standard Tests are confined mostly to the posts pertaining to Central Excise /Examiner/Prevebtive Officer , CBI and NIA profiles. Candidates being recruited for these departments will have to go through Physical Medical test to check the body's compatibility. The parameters they check are Height, Physical Standards like during walking and cycling/running, Vision and Chest measurements. Tattoos do not fall in this Category. Now having said that, for posts like in  CBI and NIA departments, there might be concerms because they are Intelligence agencies. Or else you are good. A tattoo cannot be a hindrance to your performance and you will not be judged by having a tattoo.

Hello Vivek,
Yes, Tattoos might cause you problems if you want a job in government sector, let it be banks or SSC in your case. If we talk about defense services then tatooes are a strict no-no . But if we talk about ssc then It  depends on the post you are being recruited for as well as the visibility of your tattoo.  Moreover, There is no bar in recruiting candidates in the CAPFs, Delhi police and the Central Industrial Security Force (CISF) with permanent tattoo as per the SSC recruitment rules. So you don't have to worry much.
Hope this helps.. Good luck