Hey venkata sai kumar,

the engineering entrance exams that don’t have negative marking are,

1. VITEEE 

2. TS eamcet

3. Ap eamcet

4. Comedk UGET

5.BVPEE

these are the few engineering exams which don’t have negative marks in their exam.

all the best!

As Ankit raj mentioned most of things. I would like to add some more name of exam like SRM jee and some more from following link
https://www.google.co.in/amp/s/www.shiksha.com/b-tech/articles/amp/marking-scheme-of-important-engineering-entrance-exams-blogId-7838

Respected sir,
Nearly all the exams conducted by central board like joint entrance examination or JEE mains have the negative marking.
Similarly the state board engineering entrance examination like UPSEE of uttar Pradesh,UPES for Uttarakhand,IPU for Indraprastha University delhi,KCET for Karnataka
These all exams have negative marking because by negative marking only they give the rank of students as according to question toughness level
There are only few like WBJEE has no negative marking
Rest all do have as far as i know.
Thank you

Every engineering exam have negative marking but in some state board exam like wbjee it has some questions without negative marking.
Best of luck.