'Laiyang Chili' and 'Ya Li' (Pyrus bertschneideri Reld) pears were treated with 3, 6, and 9% emulsions of commercial or refined (reduced α-tocopherol levels) plant (soybean, corn, peanut, linseed, and cottonseed) oils at harvest an stored at 0 o C for 6 months. Effects of oil treatments on ethylene production, respiration, fruit firmness, fruit color, soluble solid content (SSC), titratable acids (TA), internal browning (IB), and internal CO 2 , O 2 , and ethanol were studied. At the same concentration, oil treatments induced similar responses regardless of their sources or their α-tocopherol concentrations. In both cultivars, ethylene production and respiration in fruit treated with 9% oils were lower in early storage and higher in late storage than that in the controls. Oils at 6% reduced IB, at 9% inhibited IB completely, and at 3% was not effective after 6 months at 0 o C and 7 days at 20 o C. Plant oil treatment maintained fruit color, firmness, SSC, and TA in a concentration-dependent manner during storage. In the first 4 months storage, 9% corn oil-treated fruit contained similar partial pressure of CO 2 and O 2 as the controls. After 5 months storage, oil-treated fruit contained higher partial pressure of CO 2 and lower levels of O 2 than the controls. When held at 20 o C for 7 days, changes of internal CO 2 and O 2 were slower but partial pressure of CO 2 were higher, and O 2 were lower, in 9% corn oil-treated fruit than in the controls. Internal ethanol was not affected by oil treatment compared with control, either during storage or 7 days at 20 o C. No off-flavor was detected in either oil-treated and control fruit by sensory evaluation.