Ivaylo Petev's men, who had never before played in the top flight, overturned a two-point deficit to the country's most successful club courtesy of a goal from Miroslav Ivanov
Promoted to the top flight for the first time in the club's history last summer, Ivaylo Petev's men went into the final round of the season trailing the country's most successful side by two points in the standings.
However, Miroslav Ivanov opened the scoring for Ludogorets 19 minutes in before their visitors were reduced to 10 men when Angel Grunchov saw red for a stamp on Marcelinho just before the break.
Ludogorets' Svetoslav Dyakov then saw red as an ill-tempered affair threatened to get completely out of hand but the hosts' maintained their composure and held on to earn their first ever title.
Razgrad, who have never before played in European competition, will now go into the second round of the Champions League qualifiers.
The club, which was founded in 1945, is funded by Kiril and Georgi Domuschievi, who pumped money into the first team last year.