Yes, you can apply for China visa in Doha since you are work there. Your work visa should be valid for more than half a year.

Hello Mr.Alvin
Thanks for your reply.
Can i get Z visa from Doha. I am getting a job in China. The chinese company will be sending me the relevant documents to apply for Z visa.
What documents should i have to apply for it.

You can apply there. To apply for a Visa Z, an Employment License of the People's Republic of China for Foreigners (which could be obtained by the employer in China from the provincial or municipal labor authorities) and a visa notification letter/telegram issued by an authorized organization or company are required. Besides, you need the original passport valid for more than 6 months, two passport-sized photo, application form for P.R.China and your work visa or residence permit in Doha.