Elliptic Curve Digital Signature Algorithm (ECDSA) is implemented on an Altera Cyclone II EP2C20F484C7 FPGA using a DE1 development and education board. Digital signatures are digital counterparts of handwritten signatures. They provide proof of authorship and authenticity and they are unforgeable. They also provide proof that the document has not been altered after signing. The design includes a Nios II processor together with customdesigned modules for elliptic curve cryptography, SHA-1 hash function and modular arithmetic. A pseudo-random number generator is also included for rapid and secure generation of pseudo-random numbers. A user interface is designed with Nios II Integrated Development Environment (IDE) for demonstrating the use of the design. The design requires approximately 85 % of the device resources. Signature generation is computed in 0.94 ms and signature verification requires 1.61 ms.