In these days use of digital data exchange is increasing day by day in every field. Information security plays very important role in storing and transmitting the data. When we transmit a multimedia data such as audio, video, images etc. over the network, cryptography provides security. In cryptography, we encode data before sending it and decode it on receiving, for this purpose, we use many cryptographic algorithms. AES and DES are most commonly used cryptographic algorithms. AES provides the encryption to secure the data before the transmission and DES also provides security as AES. In this paper we discussed AES and DES and their comparison using MATLAB software .After applying AES and DES, we compare their result on the basis of avalanche effect, simulation time and memory required by AES and DES.