Abstract: A study was conducted at the Teaching and Research Farm of the University of Agriculture, Makurdi in 2007 and 2008 cropping seasons to monitor the effects of selected chemical stimulants on castor seed germination. Top paper (TP) method of seed germination according to Toogood (1993) was adopted. The chemical stimulants used included: 2, 4 – Dichlorophenoxyacetic acid (2, 4-D) @ 200mg/L, coconut milk @ 15%, aluminum tetraflouride (AlF4) @ 200mg/L, fusiccoccin (FC) @ 200mg/L, potassium nitrate (KNO3) @ 15% and ethrel @ 200mg/L. The chemical stimulants were put into 9cm-diameter petridishes, each containing ten seeds of each castor accession. Data were collected on first germination count at 7 days after planting (DAP), final germination count at 14 DAP, pre-emergence mortality at 14 DAP, post-emergence mortality at 14 DAP, and germination speed index was used to quantify seed, seedling vigour and the planting value of seed lots. Results revealed that 15% of coconut milk followed by 15% of potassium nitrate and 200mg/L of aluminum tetraflouride produced significantly higher final germination count and germination speed index but lower seed mortality rate was observed with untreated seed lot (control) and with 1% of hydrogen peroxide. Germination characteristics were not significantly different in 2007 and 2008. Year x stimulant interaction on germination characteristics was not significant in all the castor accessions studied.