It was studied the plant spacing effect (0,4; 0,6; 0,8 and 1,0m between rows) and density (2, 4, 6, 8 and 10 plant/m in row) on seed production and quality of pigeon pea (Cajanus cajan). The experimental design used at field conditions was the randomized block with a factorial arrangement 5 x 4 constituted by 20 treatments and, 3 replications blocks. According the results was concluded that: 1. The best production was obtained with the 0,4m spacing between rows with 2 plants/m in the row; 2. The germination percentage was influenced only by the spacing between rows; 3. The speed of emergence vigor index wasn?t influenced, by of plant spacing and desity, however, the first germination count and the accelerated aging test were affected them; 4. ln general, the 0,4m spacing between rows with 2 to 6 plants