Harrison is the top-rated prospect in Ohio and No. 4 in the nation in 247Sports Composite rankings.
The 6-foot-5, 243-pounder was the subject of a heated recruiting battle but little media coverage (relative to a recruit of his repute) as he rarely did interviews or provided updates on his status.
Harrison’s decision marks the 11th time in 12 years Ohio State signed the No. 1 player in Ohio.
Last year, Fairfield offensive tackle Jackson Carman bucked a 10-year trend and spurned Ohio State in favor of Clemson.
>>RELATED: Carman explains why he chose the Tigers
Prior to last year, Ohio State had signed a player ranked No. 1 by at least one of the major recruiting services every year since Ben Martin of Cincinnati La Salle chose Tennessee in 2007.
Although the share of Ohio recruits went down under head coach Urban Meyer, he typically was able to reel in the majority of the state’s very best recruits.
This season, Ohio State's class includes five of the top 10: Mansfield Lexington linebacker (ranked third), Mentor offensive lineman Ryan Jacoby (sixth), Cleveland St. Ignatius linebacker Tommy Eichenberg (eighth) and Mentor defensive end Noah Potter (ninth).
Cincinnati Walnut Hills defensive lineman Jowon Briggs, the state’s No. 2 prospect, chose Virginia while Cincinnati Anderson offensive lineman Zeke Correll (No. 4) chose Notre Dame, Akron Hoban offensive lineman Nolan Rumler (No. 5) went with Michigan, Northmont linebacker Jestin Jacobs (7) signed with Iowa and Lakota West defensive lineman Steven Faucheux (10) is headed to Purdue.