In this paper, we investigate experimentally an integrated quantum secure communication system using weak coherent state. Two modules are involved in the presented system. One is used for generating the secret key which is obtained using continuous variable quantum key distribution scheme, and the other serves to encrypt and decrypt the real-time private data using a pure quantum cryptographic algorithm. The sifted key rate with reverse reconciliation is 8.6 and 3.9 kb/s in the quantum key distribution scheme under the individual attack and the collective attack, respectively. The system uses an all-fiber dual unbalance beam Mach-Zehnder interferometer, and is implemented with a 500 kb/s modulation rate over 27.2 km of optical fiber. In this paper, we investigate experimentally an integrated quantum secure communication system using weak coherent state. Two modules are involved in the presented system. One is used for generating the secret key which is obtained using continuous variable quantum key distribution scheme, and the other serves to encrypt and decrypt the real-time private data using a pure quantum cryptographic algorithm. The sifted key rate with reverse reconciliation is 8.6 and 3.9 kb / s in the quantum key distribution scheme under the individual attack and the collective attack, respectively. The system uses an all-fiber dual unbalanced beam Mach-Zehnder interferometer, and is implemented with a 500 kb / s modulation rate over 27.2 km of optical fiber.