NOVELTY - Cultivation of bonsai-type Pleurotus ostreatus comprises inoculating culture medium at 22-28 degrees C for 5-8 days until hyphae overgrow with culture medium inclined plane to obtain mushroom parent mycelium; adding with culture medium in test tube and culturing at 23-32 degrees C for 32-38 days at 60-70% humidity to obtain mushroom mycelium stock seed; inoculating in the light at 20-27 degrees C and culturing for 28-32 days; and adding nutrient solution and light culturing at 20-25 degrees C.    USE - Method for cultivating bonsai style Pleurotus ostreatus (claimed) used for small-scale family-style cultivation.    ADVANTAGE - The method produces bacteria-free mushroom fruit, high yield and quality mushroom, reduces use of fungicides and pesticides, has no stimulation, no pollution, and no residue, promotes more comprehensive mushroom nutrient absorption, and improves productivity of mushroom.    DETAILED DESCRIPTION - Cultivation of bonsai-type Pleurotus ostreatus comprises:    (A) inoculating culture medium at 22-28 degrees C for 5-8 days until hyphae overgrow with culture medium inclined plane to obtain mushroom parent mycelium, where culture medium comprises 150-300 g potato, 10-30 g dextrose, 5-20 g peptone, 800-1200 mL sterile water, and 10-40 g agar powder;    (B) adding with culture medium in test tube and culturing at 23-32 degrees C for 32-38 days at 60-70% humidity to obtain mushroom mycelium stock seed, where culture medium comprises 65-95% cotton seed hull, 10-30% wheat bran, 0.5-5% gypsum, and 60-70% sterile water;    (C) inoculating in the light at 20-27 degrees C and culturing for 28-32 days, where humidity is 55-85%, where culture medium comprises 70-98% cotton seed hull, 1-10% wheat bran, sucrose, gypsum, and 0.5-5% lime and pH value is 7-8; and    (D) adding nutrient solution and light culturing at 20-25 degrees C, where nutrient solution comprises 450-550 mg magnesium sulfate, 750-850 mg potassium nitrate, 900-1000 mg calcium nitrate, 140-160 mg potassium dihydrogen phosphate, 10-30 mg EDTA ferric sodium salt, 1-5 mg boric acid, 1-5 mg manganese sulfate, 0.2-0.3 mg zinc sulfate, 0.01-0.1 mg copper sulfate, and 0.01-0.05 mg ammonium citrate in 1 L solution.