Can foreign citizen/national become the partner in indian partnership firm? kindly guide me in details with regards to fema and fdi rules and regulations

Yes, a Foreign Citizen can be a Partner in Indian Partneship Firm.

According to Foreign Exchange Management (Investment of Firm in Proprietary in India) Regulations, 2000 Only a Non-Resident Indian (NRI) or a Person of Indian Origin (PIO) resident outside India can invest in the capital of a firm or a proprietary concern in India on non-repatriation basis subject to the following conditions;

1. Amount is invested by inward remittance or out of NRE/FCNR(B)/NRO account maintained with Authorized Dealers/authorised banks. 2. The firm or proprietary concern is not engaged in any agricultural/plantation or real estate business or print media sector.  3. Amount invested shall not be eligible for repatriation outside India. (Section 4).

Section 5 - A firm or a proprietary concern in India may make payment to or for the credit of a nonresident Indian or a person of Indian origin the sum invested by such person in that firm or the proprietary concern or the income accruing to such person by way of profit on such investment.