Business Visa

Generally, a China Business Visa Invitation Letter is needed and one of the following is required:

1). Invitation letter issued by a Chinese business or trade partner.
2). Invitation letter or confirmation letter of invitation issued by duly authorized Chinese institutes or relevant units.
3). Invitation letter of a trade fair.

Other than that, you need to prepare some normal documents like valid passport, photos, a completed Visa Application form, etc. Remember to make an online appointment in advance to lodge the submission.

is it possible to apply for 2 years?

Generally, the duration is 30 - 90 days.