The problem that often arises in the procurement of seeds is in selecting seeds that have high physiological quality. The Porang (Amorphophallus muelleri Blume) planting material is generally in the form of bulbils of varying sizes with a dormancy period of 4-5 months. One of the efforts to break seed dormancy is by soaking. This study aimed to determine the effect of bulbil weight and soaking duration on the viability and growth of porang. The research was carried out at the Pakuwon Experimental Station, Balittri, Sukabumi, West Java, from September to December 2020. The design used was a split plot with 3 replications. The main plot was the bulbil weight which consisted of 3 categories: (1) large size (12.66-16.96 g/seed), (2) medium (10.41-11.53 g/seed), and (3) small (5.63-7.11 g/seed). The sub-plots were the soaking duration in water which consisted of 4 levels: 0 hours (without soaking), and soaking for 2 hours, 4 hours, and 6 hours. The variables observed were the viability, petiole length, and fresh weight of plants at 2 months after sowing. The results showed that there’s no interaction effect between bulbil weight and soaking duration for all variables observed. Bulbs with large and medium weights produced higher viability and petiole length compared to small bulbils, while the highest plant fresh weight was produced by large bulbil weights. The correlation results showed that the higher the viability of the seed, the longer the petiole, and the higher the fresh weight of plant.