We numerically investigate the effects of reactor wall temperature profile and seed particle; addition on particle growth and deposition in a hot-wall tubular chemical vapor deposition reactor. Five reactor wall temperature profiles are studied, including (i) isothermal, (ii) linear decrease, (iii) linear increase, (iv) linear decrease followed by linear increase, and (v) linear increase followed by linear decrease. For the study of seed particle addition, the effects of seed particle concentration, size, and size distribution are investigated. It is found that profile iii gives the largest product particles. while profiles i and v Produce the most narrowly distributed product particles. Also profile v results in the highest deposition ratio. The geometric mean size of product particles increases with increasing seed particle concentration, but the product particle size distribution will become narrower only when the seed particle concentration is high enough. The mean size and size distribution of seed particles have almost no effect on particle growth and deposition under the operating conditions investigated. Deposition ratio and deposition flu,: uniformity are not affected by seed particle addition, but are greatly influenced by reactor wall temperature profile. The variation in deposition ratio, geometric mean diameter, and geometric standard deviation of the resulting particles is attributed to a competition of chemical reaction, Brownian coagulation, diffusive deposition, thermophoretic deposition for the temperature profile study, and to scavenging of Small clusters by seed particles for the seed particle addition study.