Many algae were found to be able to survive desiccation. When studies were done to identify the specific cellular responses induced by dehydration, it had been generally assumed that the majority of the cell population could survive the stress, so that the responses found were related to the mechanism of desiccation tolerance. However, we report here a case of newly-isolated Chlorella species that has the ability to tolerate desiccation and restart growth upon rehydration. A close examination of the changes of cellular chlorophyll and DNA contents during the course of growth resumption by flow cytometry reveals that the new growth starts from only a few cells, i.e. the majority of the cells lose their ability for reproduction after stress. Therefore, a check on the ability of revival of the cell population after stress seems to be worthwhile and flow cytometry is a convenient tool for following various changes in cells of a population during the whole course of stress application and recovery.