Hi I am planning to change my status from b2 to H1b while I am on b2 and after H1b is approved I want to bring my wife to us ; how will that work ?

Your difficulties appear to be multiple – the first being that a B-2 visitor is not supposed to come to the US with the intention of changing status from B-2 to H-1B. Such is considered an abuse of the visa. The second problem is one of timing unless you will be applying for an H-1B specialized occupation job at a cap exempt employer, e.g. institution of higher education. Otherwise the period of time to apply for cap limited visas is the first five business days of April, and that time has already expired. Please also note that if you were to enter the US next year and attempt to change status through applying for an H-1B petition, you would have to maintain a legal status until at least October 1, when persons who have been approved can legally begin to work. The filing does not freeze your legal status because the benefit is not available until the fiscal year begins in October. Due to the limitations of the Lawyers.com Forums, Alan Lee, Esq.'s (the "Firm") participation in responding to questions posted herein does not constitute legal advice, nor legal representation of the person or entity posting a question. No Attorney/Client relationship is or shall be construed to be created hereby. The information provided herein by the Firm is general, and requires that the poster obtain specific legal advice from an attorney. The poster shall not rely upon the information provided herein as legal advice nor as the basis for making any decisions of legal consequence.