This research study examined how adjunct professors have applied online teaching practices and perceived the impact of professional development on those practices. A purposeful sampling of online adjunct instructors from two adjunct-focused Facebook groups was used to collect survey data. An adapted 30-question instrument was administered via Qualtrics. The relationships between the dependent and independent variables were conducted using descriptive and inferential statistics with IBM® SPSS Statistics 27. Data was analyzed using regression, correlation, t tests, and ANOVAs. Quantitative results indicated that there is a positive relationship between online teaching practices and perceived impact of professional development for adjunct instructors.