Shares were falling 2.3% to $154 in premarket trading.
The Goodlettsville, Tennessee-based discount retailer reported net income of $535.4 million, or $2.10 a share, up from $483.2 million, or $1.84 a share, a year ago. Analysts expected earnings of $2.01 a share.
Sales totaled $7.16 billion, up from $6.65 billion a year ago and ahead of analysts' estimates of $7.15 billion in sales. Same-store sales rose 3.2%, beating forecasts of 2.8%.
"Our full-year results were highlighted by double-digit diluted EPS growth, as well as our 30 consecutive year of same-store sales growth," CEO Todd Vasos said in a statement. "During the fourth quarter, we delivered a healthy 3.2% increase in same-store sales, as well as strong margin performance."
The company's board declared a quarterly cash dividend of 36 cents per share, up 12.5% from a year ago.
Looking ahead, the company expects fiscal 2020 sales growth to range from 7.5% to 8%, and same-store sales growth of 2.5% to 3%. Earnings per share are projected to grow 11.5%.
Addressing current health concerns, Dollar General said that based on management's current information, "the company does not anticipate that supply chain disruptions experienced to date as a result of the coronavirus outbreak are likely to have a material impact on its fiscal 2020 financial results."
"However," the statement continued, "the company continues to monitor this evolving situation, and there is no guarantee that this outbreak will not have a more significant impact on its business."