The monoterpenoids are analysed in leaves and fallen leaves of Pinus species (P. thunbergii, P.. rigida. P. densiflora.). The amount of total monoterpenoids of P. thunbergii was always the highest, and then those of P. rigida and P. densiflora were orderly decreasing (P<0.05). The major monoterpenoids of P. thunbergii, P. rigida and P. densiflora are ${eta}-pinene$, comphene and sabinene. There was no significant difference among the seasonal variation in monoterpenoids composition (P>0.05), but the concentrations of fenchone and bornyl acetate were varied (P<0.05).