Different chitosan preparations were investigated for their effect on orchid meristem culture and orchid protocorm propagation in liquid and on agar media. According to the results obtained, chitosan has the ability to stimulate the induction of the differentiation of orchid plant tissue. Fungal chitosan and shrimp oligomer chitosan of 15 and 20 ppm are most effective on protocorm propagation in liquid and on agar orchid plant tissue culture media, respectively.