Hai, I am karthik, kindly help me for the better career objective to write in my CV for IT industry in Marketing.

I am having more than 3 years Exp in Marketing but very new to the IT.

Here are some good points to consider and expand on:
How to Write a CV (Curriculum Vitae) - wikiHow

A CV is similar to a Resume in that you want to be sure to show yourself in the best light as possible while keeping it concise.