We present an improved eavesdropping scheme on the quantum dialogue protocol in lossy channel, which is based on the strategies of Wójcik Phys. Rev. Lett. 90 157901 (2003)] and ZML Phys. Lett. A 333 46 (2004)] attack schemes. We show that our attack scheme doubles the domain of Eve's eavesdropping and Eve can gain more information of the communication with less risk of being detected. Finally, a possible improvement for the dialogue protocol security is proposed.