This paper proposes the use of luni-solar gravity assists for asteroid retrieval. The joint lunar and solar gravity assist can be approximated by a sequence of Moon-Moon transfers, in which the solar perturbation is effective, and lunar swingbys. The trajectory design is to find a sequence that can reduce the v∞ of the asteroid with respect to the Moon to a low level, such that the asteroid can be inserted to a lunar orbit with little effort. In this way, the Earth is kept safe from the asteroid. To aid the trajectory design, a database of Sun-perturbed Moon-Moon transfers is used. However, it is burdensome to compute optimal heliocentric transfer trajectories and capture trajectories for every asteroid in the large near-Earth asteroid database. This paper presents analyses revealing the capture capacity of luni-solar gravity capture in terms of Jacobi constant, the magnitude and declination of the v∞ of the asteroid with respect to the Earth. With this information known, the asteroid candidates can be easily selected out. It is found that there are 13 asteroids that can be retrieved by a mission during the period from 2020 to 2030.