Distribution of catecholamine-containing cells in the adenohypophysis of the White leghorn fowls was studied after administration of L-dopa. Results obtained in this study are as follows: 1. In control cocks and hens, no catecholamine-containing cells were observed. 2. After administration of L-dopa, green fluorescent cells were observed in the cephalic lobe in cocks and immature pullets. It is considered that these cells are ACTH cells and therefore included into the APUD cells described by Pearse (1968, 1969). 3. In addition to ACTH cells in the cephalic lobe described above, another type of green fluorescent cells identified with GTH cells were observed in the both cephalic and caudal lobe in the laying hens. This result suggests that the uptake of L-dopa or dopamine into GTH cells can be probably related to LH secretion during the ovulatory cycele.