Lake Sturgeon (Acipenser fulvescens) are a threatened fish in New York State due to historical overfishing and habitat loss. Despite conservation efforts, significant knowledge gaps persist regarding population abundances, age structure, and growth rates. This study helps to address these gaps by developing an age-length key for Lake Sturgeon in New York State. Long-term Lake Sturgeon monitoring data from Oneida Lake, Genesee River, and the Niagara River were analyzed to compare population growth and determine if population specific age-length keys were needed. Size-at-age analyses and von Bertalanffy growth curves were used to assess differences among populations. Results showed significant differences in size-at-age among populations, with the Genesee River population exhibiting the smallest mean lengths at comparable ages. Von Bertalanffy growth curves further highlighted population-specific growth. Age-length keys were found to have varying degrees of accuracy in predicting fish ages. While age-length keys offer a time-efficient and cost-effective alternative to traditional aging methods, caution is advised in their application for Lake Sturgeon in New York.