Solar sail is a propulsion engine using no fuel because it can receive photon momentum. Japan Exploration Agency (JAXA) proposes solar power sail as a new propulsion engine for deep space explorations. It can be a hybrid engine, if the ion-propulsion engines, whose specific impulse is very high, are driven by the solar cells on the membrane. JAXA is studying two missions to demonstrate solar power sail as shown in Fig. 1. Small-sized solar power sail in the early 2010s is the front-loading measures for risk reduction. The minimum success criteria are the deployment of the sail whose diameter is 20m and electric power supply using the solar cells on the membrane. The full success criteria are the acceleration and navigation using photon sail for the first time. On the other hand, the medium-sized solar power sail in the mid-2010s integrates ion-propulsion engines with solar power sail of diameter 50m. The destinations of the spacecraft are the Jupiter and the Trojan asteroids. Some kinds of deployment methods have been investigated[1],[2]. JAXA is studying the spinning type, in which the membrane is deployed and maintained flat by the centrifugal force. This method is expected to be realized with simpler and lighter-weight mechanism than other ways, because it does not require rigid structural elements. The authors have been demonstrating it. The dynamic deployment of φ10m sail was performed successfully using an S-310 sounding rocket at 08/2004 [3]. The static deployment of φ20m sail was demonstrated using a high altitude balloon at 08/2006 [4]. In this paper, the sail shape and equipment layout for small-sized solar power sail mission are proposed. The deployment method, sequence and mechanism are also introduced. The deployment motions are analyzed by numerical simulations using multi-particle models in order to verify the deployment.