You must have the following requirements to apply for a USA Business visa:
- An original & valid passport
- A fully-filled DS-160 Form
- Visa application fee receipt
- Copies of your latest passport-sized photographs
- Evidence of funds to support your stay in the US
- Letter from your employer in the US
- An invitation letter from the company in the US
- Proof of your business in your home country (registration documents)
- Evidence of ties to your native country (proof of home ownership, employment contracts in your country, etc.)
- Clear criminal record (if required)