Abstract: In order to further explore the relation between browning spot incidence on fruit peel of ‘Huangguan’pear and calcium nutrition，Ca compounds in‘Huangguan’pear fruit were gradually extracted and determined under investigation of browning spot. The results showed that browning spot incidence on fruit peel of three-layer bagged mature fruit was 22.5%，and the rate of non-bagged mature fruit was 1.5%. There were no significant differences in the contents of calcium in total and different forms in fruit with different bagging treatment before the stage of enlargement. However，from the stage of fruit enlargement till mature，contents of total calcium，water-soluble calcium，NaCl soluble calcium and acerate calcium were significant lower，while the content of hydrochloric soluble calcium was significant higher in three-layer bagged fruit than that in non-bagged fruit. In the later stage of fruit development，water-soluble calcium in non-bagged mature fruit was dominated，accounting for 45.6% of total calcium，however，instead of water-soluble calcium，hydrochloric soluble calcium was dominated and accounted for 47.7% of total calcium in three-layer bagged mature fruit. Through multiple stepwise regression analysis and path analysis，it was found that water soluble calcium，NaCl soluble calcium and acetate soluble calcium had significant negative correlation with browning spot incidence，among which negative effect of NaCl soluble calcium was the largest. HCl soluble calcium had significant positive correlation，and total calcium had not significant effect on browning spot incidence.

Key words: pear, fruit bagging, calcium, browning spot