Russian legislation, law enforcement practice and legal science are actively developing the legal regulation of loan relations not only in the field of contractual, but also corporate and investment relations. Objectively, the loan has outgrown the monetary sphere and the legal relationship of obligations for the temporary, refundable and reimbursable use of other people's funds. In the modern economy, a loan is in demand as a universal means and form of lending and asset turnover with the formation of individual registration of the goals, rights and obligations of participants. The general orientation and purpose of improving Russian legislation should be considered to provide new opportunities for entrepreneurship when using borrowed instruments, provided that equality and protection of its participants are guaranteed. The article analyzes the loan issue by entities for carrying out entrepreneurial activities in various organizational and legal forms. The authors investigate the admissibility of loans by participants of a commercial corporation, propose criteria for the admissibility of loans from participants and describe situations when such loans are subject to judicial reclassification. The authors concluded that in the absence of corporate obstacles (the charter does not contain a ban on making contributions to the company's property; the need for property is permanent; all participants of the company are ready to finance its activities, etc.), then the establishment of repayment of deposits contradicts the essence of corporate relations, violates the interests of the company and its creditors. The authors noted the risks of mixing corporate and contractual relations, and assessed the convertible loan agreement.