The invention discloses a process method for removing heavy metal lead in exhaust gas. The process method comprises the following steps: adopting sodium bicarbonate as a bed layer for absorbing particle-state lead Pbp in the exhaust gas, adsorbing the particle-state lead Pbp by utilizing the gap of sodium carbonate obtained through a pyrolytic reaction between sodium bicarbonate and exhaust gas, and translating element-state lead Pb<0> in the exhaust gas into oxidation-state lead Pb<2+> by utilizing the active oxide matter produced through oxidation reaction, and taking a mixed solution prepared by adding water into sodium bicarbonate and oxidized sodium bicarbonate after pyrolytic adsorption as a spraying solution to sufficiently contact with the exhaust gas to remove the oxidation-statelead Pb<2+> in the exhaust gas and the particle-state Pbp which is not removed in the previous step and less element-state Pb<0>. Compared with the traditional lead removing process, the defect that the traditional process method is generally low in lead removing efficiency is remedied; a spraying operation running process is free from scaling and blocking risk, the process method is insensitive to the exhaust gas fluctuation, and the device adaptability is good; the problems of the denounced secondary sewage and secondary solid-waste pollution of the wetting method are overcome, and the process method has good economic benefits and environment benefits.