Alcaligenes sp.의 인 제거에 대한 환경인자로 각각 온도, pH, 탄소원의 효과를 알아본 결과 $25^{\circ}C$, pH 7, glucose+acetate이 탄소원일 때 인 제거효율이 가장 좋은 것으로 확인 할 수 있었다. 5가지 중금속의 독성효과에 따른 Alcaligenes sp.의 생장은 중금속의 농도가 높아질수록 억제되었으며, $IC_{50}$값은 구리 5.03 mg/L, 카드뮴 0.08 mg/L, 아연 0.73 mg/L, 비소 282.20 mg/L, 니켈 4.74 mg/L로 나타났다. 모든 중금속의 농도가 높아질수록 생장이 억제되어 인 제거 역시 억제되는 것을 확인 할 수 있었다. BACKGROUND: This study was performed to evaluate the effects of environmental factors and heavy metals on the growth and phosphorus removal capacity of Alcaligenes sp., which was well known as one of PAOs(Phosphorus Accumulating Microorganisms). METHODS AND RESULTS: The environmental factors used in this study were temperature, pH and carbon sources, and the heavy metals included Cu, Cd, Zn, As, and Ni. The growth and P removal efficiency of Alcaligenes sp. was maximal as temperature, pH, and carbon source were $25^{\circ}C$, 7, and glucose+acetate, respectively. Also, the $IC_{50}$(median inhibitory Concentration) values of Alcaligenes sp. for the Cu, Cd, Zn, As, and Ni were 5.03, 0.08, 0.73, 282.20 and 4.74 mg/L, respectively. CONCLUSION(S): Based on the results obtained from this study, it appears that the growth and P removal efficiency of Alcaligenes sp. were affected by the environment factors and at the best optimum condition for its growth and P removal efficiency, as the concentrations of heavy metals were gradually increased, its growth was correspondingly decreased.