Mr.kishan, if your company or employer who apply for the business visa for you, your wife can stay with you in China for 9 months, if your wife apply for tourist visa, Unless specifically requested by your wife in her completed application form and approved by consular officers, a single-entry visa is valid for 3 months with a 30-day duration of stay. The tourist visa can only be extended for 2 times, 30 days stay duration each time, then there are 90 days stay duration in total.