Forming limit diagram (FLD) is an effective tool to evaluate the limiting strain in various conditions. In this study the formability of tantalum has been investigated and led to forming limit diagram of tantalum. For this propose three groups of tests has been carried out on the tantalum. At first, Erichsen test has been performed on sheets of tantalum to obtain the forming limit diagram (FLD). Then for evaluating the result of Erichsen test, compression test has been carried out. The obtained FLD of Erichsen test presented a good conformity with the FLD from compression test. In addition, the strain-hardening exponent, n, for tantalum has been obtained from tensile test. The n value from results of tensile test is close to the minimum point of forming limit diagram that indicate the strain-hardening exponent.