An in vitro fruiting system was established for the orchid Erycina pusilla and substantial seed production was achieved. In contrast to other orchid in vitro flowering systems, pollen tube growth and fertilization were successful after hand pollination in vitro. Germinated pollen tubes were observed on stigmas four days after pollination (DAP), and penetrated into the ovaries between seven and fourteen DAP. Zygotes were observed in embryo sacs 3-4 weeks after pollination (WAP). Fruits began to develop six WAP, with seeds containing a minute embryo, however, unable to germinate. The seed germination percentage was 7.5% at eight WAP and 39.4-62.7% between ten to fourteen WAP. The fruits could generate more than 63,838 seeds per capsule and more than 95% of the seeds contained an embryo. This reliable method of in vitro fruiting and seed production could be very useful in Oncidiinae breeding in the future.