The honeysuckle leaf-miner Phytomyza lonicerae repeats two generations from winter to spring on Lonicera gracilipes in undergrowth of natural deciduous forests near Kyoto, Japan. From February to March, when available host leaves are scarce in the forest, aggregative distribution of eggs laid into immature leaves results in a great mortaility of the first generation larvae due to exploitative competition among larvae in small leaves. Twenty-one hymenopteran species, 3 of which belong to Braconidae, 1 to Pteromalidae and 17 to Eulophidae, were found from the leafminer. Twelve species of them were larval, 3 larval-pupal and 6 were pupal parasitoids. High species diversity in the parasitoid complex is discussed with reference to the competition among the species and comparative tactics of them.