During his service, he was wounded in the Battle of Brandywine and was part of the encampment at Valley Forge 1777–1778.
He was part of the southern Campaign under Gen. Nathaniel Green. After the Battle of Yorktown, he returned to York County, Pennsylvania. He was discharged from the Army in 1783.
Ralston married Sophia Waltemier (Waltemyer) in December 1785. She was the daughter of David Waltemier (Waltemyer), who was also an American Revolutionary soldier. The Ralstons were the parents of 11 children. In 1812, they moved from York, Pennsylvania, to Jefferson County, Ohio, where they lived on a farm.
Their 11 children were:
David Ralston 9-2-1786
Margaret Ralston 10-28-1788
Mary Ralston 12-26-1790
Elizabeth Ralston 2-8-1790
Jane Ralston 11-13- 1794
Andrew Ralston II 2-7-1797
John Ralston 7-13-1799
Catherine Ralston 11-29-1801
Ann Ralston 7-10-1804
Lewis Waltemyer Ralston 11-30-1806
Nancy Ralston 6-22-1809
Andrew Ralston, a soldier of the American Revolution, died on September 11, 1827. He and his wife are buried in Beach Spring Presbyterian Cemetery, Harrison Co., Ohio.