“Ping-pong” protocol is a novel secure deterministic quantum communication protocol. Based on an entangled pair of qubit, it allows asymptotically secure key distribution and quasi-secure direct communication. Its absolute security has been proved. It is hoped that this kind of quantum deterministic communication will be a main trend of the future quantum optic communication. However, there is no experimental implement of this protocol reported so far. The working scheme of the ping-pong protocol is analyzed and its flow chart is presented. Then the scheme of physical realization of the ping-pong protocol is analyzed. Combining entangled photon resource technique with single photon routing control and single photon detecting technique, an experimental realization in freespace of this protocol and its equipment figure are then proposed. Based on this work, further research of the ping-pong protocol and some practical applications can be taken.