Leasing is a contract by which the tenant becomes the owner of the usufruct of the leased property. The purpose of the present research is to examine the conditions of leasing from the perspective of jurisprudence and law. The research method is descriptive-analytical and uses library resources. From the perspective of Shiite jurists, there are many differences between sale and leasing, including in a sale, the seller directly sells the usufruct, but in leasing, the lessor empowers the lessee to use the property. Sale is the subject of the transfer of ownership, while leasing is the subject of the transfer of usufruct. Specifying the duration in leasing is a condition of the validity of the contract, and its absence causes the invalidity of the contract. Leasing, like sale, is a transferring contract, and its effect is the transfer of usufruct to the lessee, meaning that after the contract, he becomes the owner of the usufruct of the leased property or, in other words, during the lease period, he uses the same authority and rights as the owner and takes control of the right to benefit from the property. In leasing, the transfer of usufruct is done in exchange for a certain consideration, meaning that the lessee also gives or undertakes to pay a certain amount to the lessor.