This study aimed to identify the prevalence of current smoking and examine the association between meeting combinations of the 24-h movement guidelines and current smoking in autistic adults. This cross-sectional study administered an electronic survey to a national sample of autistic adults in the United States. The study outcome was current smoking. Independent variables included the 24-h movement behaviors. Multivariable statistical modeling was used to assess the study aims. The study sample (n = 259) had a mean age of 31.05 years (standard deviation = 7.70), 58.7% were male, 11.2% were fully independent, and 35.5% were current smokers. Current smokers met significantly fewer 24-h movement guidelines than non-smokers (mean = 1.52 (standard deviation = 0.73) vs mean= 1.93 (standard deviation = 0.88), respectively, t = 3.77, p < 0.01). Autistic adults with high levels of sedentary behavior were almost three times more likely (odds ratio = 2.784, 95% confidence interval = 1.490, 5.237) to be a current smoker than those who did not meet these guidelines. Autistic adults not meeting sleep and sedentary behavior recommendations had a 1.581 increased odds (odds ratio = 1.581 95% confidence interval = 1.25, 2.001) of being a smoker as compared to those meeting these recommendations. Current smoking was highly prevalent in this sample. Improving sleep health and reducing sedentary time may be viable intervention targets to help promote smoking cessation in autistic adults.