The biodegradability of different plastic material was investigated under aerobic conditions. The samples were placed in the compost pile and were checked over 15 weeks. After the expiration of the experimental period it was found that the samples with the additive (samples 1, 2, and 3) had not decomposed, their color had not changed, and that no degradation or physical changes had occurred. SEM photomicrograph images of the surface of the samples confirm this statement. Samples 4, 5, 6, and 7 (certified as compostable) were decomposed. Samples 5, 6, and 7 exhibited the highest decomposition rates. The SEM observation showed that the film surface of the samples was totally eroded and its smoothness disappeared. The present study suggests that the biodegradable characteristics differed significantly depending on the type of biodegradable/ degradable plastics.