Abstract: Puffballs of Pisolithus tinctorius were used to prepare spore slurry with loess and tap water (1:2:100). The spore slurry was then inoculated onto the container-grown Caribbean pine seedlings which were growing at six different concentrations of phosphate fertilizer-calcium, superphosphate. The results showed that both in nursery and field, the pine seedlings inoculated with P. tinctorius performed much better than the uninocu-lated ones, especially in root collar and dry weight. Meanwhile, the application of phosphate fertilizer at the proper concentration could accelerate the growth of inoculated seedlings. Generally, the pine seedlings inoculated with P. tinctorius at the concentration of 0.5%~7.0% calcium superphosphate would grow the best.