Dear Aspirant,

You will not be able to join ISRO only after your diploma You must have to  have completed your graduation or post graduation to get a job in ISRO.

BTECH:-

After completing B.Tech from any college, an examination namely ICRB (centralized Recruitment Bangalore) is conducted by ISRO and individuals are tested as per their respective branches of engineering and after clearing the interview, one can get appointed as a scientist or an engineer at ISRO. Candidates must have a minimum aggregate percentage of 65% and above in B.tech in their respective relevant streams.

MTECH:-

After the completion of M.Tech in trades such as Geoinformatics, Remote Sensing, Instrumentation, applied Mathematics, Geophysics, Geography or any other equivalent degree in the field of Physics or Mathematics one can apply directly for the job of a scientist at ISRO. The selection consists of the written exam and Interview and after clearing these sages scientist/Engineer position can be obtained in ISRO .

Hope this helps. Thank you.