Public key cryptography is an asymmetric scheme that uses a pair of keys for encryption: a public key, which encrypts data, and a corresponding private, or secret key for decryption. Some examples of public-key cryptosystems are Elgamal, RSA, Diffie-Hellman, and DSA. Speed public key encryption scheme is a constraint on the exchange of confidential information between the two processes requiring high speed such as requirements on the Secure Sockets Layer (SSL) protocol, where one server is serving requests more than one client using public key encryption scheme , so that the whole will using a very large processing time and slow down the whole process .This research will be done to the literature study methods of Chinese Remainder Theorem ( CRT ) for the analysis of the acquisition of the operating speed of encryption / decryption RSA . To speed up the RSA decryption operation using a CRT , then we can divide a large modulo exponentially into two much smaller exponential , one on top p and one on the top q , where n = pq. Two modulo n this is the main factor that is recognizable . Further reducing the size of the problems with the use of Fermat 's Little Theorem . So the size n is 1024 bits that had been split into 512 to the size of p and q . Based on the literature study , it can be obtained by an alternative means the increase in the speed of encryption/decryption using RSA with CRT method, ie by reducing the size of the exponent .