Koroljov was born on December 24th, 1938 in Moscow.
In 1958,  Koroljov  enters the Moscow Chajkovskij Conservatory and studies with G. I. Titsa.  
He finishes in 1965.
In 1963, Koroljov takes part in the International Schumann Competition in Zwickau.  He obtains one of the six honorable mentions.
In 1964, Koroljov  participates in the International Enescu Competition  in Bucharest and obtains a laureate title (6th place).
During his time at the conservatory, Koroljov takes active part in the work of the operatic studio, where he prepares such 
operatic roles as Lenskij, Almaviva, Rodolfo, Antonio (Obruchenie v monastyre/Betrothal in a monastery) with the conductors A. 
Shereshevskij and E. Ratser.
At the beginning of the season 1964/65, while still a student,  Koroljov was accepted as a soloist by the 
Stanislavskij and Nemirovich-Danchenko Moscow Musical Theater. During that season, 
he sang Lenskij, Ferrando. Ljonka (V burju/Into the
 storm by Tikhon Khrennikov), Pavka (Semya Tarasa/The  Taras family  by Dmitrij Kabalevskij).
In 1964, Koroljov is invited to sing Lenskij at the Bolshoj. 
That role will be important throughout his career.
In 1965, after singing Duca in Rigoletto,  Koroljov is accepted by the Bolshoj.
In the fall of 1966, Koroljov takes part in the International Radio Corporations Competition in Munich and gets the first 
prize.
The German press wrote:
Münchner Merkur,  September 24, 1966: We discoverd a first class singer, the  Russian 
Denis Koroljov, who  is already a soloist at  the Bolshoj. In the cavatine from Prince Igor,  we hear a 
bright melodious sound, a beautiful lyric voice with a top with heroic nuances, and a rock solid bottom.
Augsburger Allgemeine,  September 28,  1966: Victorious competitor in the competition of singers was Russian Denis
 Koroljov, tenor with an excellent soft voice.
Bayerische Staatszeitung,  September 30, 1966: The listeners without hesitation gave preference to
 the  unconditionally very likable tenor Denis Koroljov after a dignified  execution of his aria (USSR – first prize).
The Soviet press did not miss the event. So the newspaper Pravda wrote on on September 21, 1966: Among the singers the first
 prize went to the Bolshoj tenor Denis Koroljov, who had enormous success wiht the 
 cavatine from Prince Igor.
The newspaper Soviet Culture wrote on September 24,  1966 an article Victory of Soviet musicians:
 Among the 96 young singers, two were from the USSR: D. Koroljov and the soloist of the 
Leningrad choir, G. Seleznev. The lyric tenor Denis Koroljov especially successfully sang  works by Schubert,
 Mozart, and the arias of Vladimir in Prince Igor and of Lenskij. After demonstrating his pleasant 
 timbre and high musical culture, Koroljov received the first prize.
 
 In 1967 in the competition Schubert and the XX century,  Koroljov got the 2nd prize. The special feature 
 of that complex competition consisted in the fact that together with Schubert's lieder, it was necessary to perform works of 
 contemporary composers, such as Krenek, Berg, Hindemith.
In 1970, Koroljov begins to work with the concert master of the Bolshoj orchestra, T. Z. Mosesova. In their joint programs were 
Russian romances, works by  Western and Soviet composers. Those concerts were given  in Moscow, Leningrad, Kostroma, Novosibirsk, 
Erevan 
 and abroad. The two were later married.
 
During his years at the Bolshoj,  Koroljov sang lyrical roles: Duca (1966),
 Almaviva (1966),  Alfredo (1966), Indian Guest (1966), Simpleton (1968),  
 
  Lykov (1970), Anatol Kuragin (1975), Markiz (Igrok, 1975), Manilov (creator of the role in Mjortvye dushi/Dead souls by Rodion 
Shchedrin, 1977), 
	 Mozart (1977), Ferrando (1978), Mikola (Semjon Kotko by Prokofyev, 1970), Berendej (1978); Zinovij Borisovich (Katerina 
Izmajlova, 1980), Antonio (Obruchenie v monastyre, 1983, )...
	 
		 Among Koroljov's partners were: G. P. Vishnevskaja, E. V. Obraztsova, 
		 E. E. Nesterenko, A. P. Ognivtsev, Ju. A. Guljaev,  Ju. A. Mazurok, B. A. Rudenko, G. V. Olejnichenko,
		  A. A. Ejzen, T. I. Sinjavskaja, G. K. Ots, ....
			
 Koroljov toured the USSR: from Riga and Tallinn to Chita and Jakutsk, from Leningrad to Ashkhabad and 
Frunze. He also toured foreign countries: Hungary, Poland, GDR, Bulgaria, Romania, France, FRG, Austria,
 the USA, Italy, ... 
In 1975, the Bolshoj  was invited to tour the USA for the first time.  Koroljov sang the following roles:  
Markiz, Anatol Kuragin, Lenskij, and Simpleton. After each 
performance, he was positively acknowledged by the American press.
The New York Post wrote  on July 12, 1975: An exceptional lyric tenor that would bring 
any opera house honor.
The Daily News wrote on June 30, 1975: The high, beautiful, powerful lyric tenor of Denis Koroljov is ideally  suitable for 
Lenskij. In  order to find an  equal talent, it is  necessary to go back to Ivan Kozlovskyj's records...
The  Daily News wrote on July 6, 1975: ... and Denis Koroljov  again repeated his excellent Lenskij.
The New York Times wrote on  June 29,  1975: Denis Koroljov as Lenskij  possesses an  attractive
 beautiful tenor,
 which he uses very expressively and emotionally...
The New York Post wrote on June 30, 1975: Denis Koroljov as Lenskij  was extremely attractive,  by his beautiful 
face, by his interpretation of the role, by his  beautiful voice and by the lyricism of his performance.
Koroljov's recordings include:
V burju (Ljonka,  conducted by G. P. Provatorov); Skupoj rytsar/The miserly knight (Alber, conducted by 
G. Rozhdestvenskij); Igrok/The gambler (Markiz, conducted by A. Lazarev), Die lustige Witwe (Camille de Rosillon, conducted by 
A. Mikhajlov).
With Melodija, Koroljov recorded arias, romances, lieder by M. I. Glinka, P. I. Chajkovskij, S. 
Rachmaninoff, G. V. Sviridov, F. Schubert, R. Strauss.
Koroljov participated in concerts with orchestras of the All-Union Radio and Television, 
 singing  Russian and Soviet songs.
For many years, Koroljov taught singing at the Moscow Chajkovskij Conservatory.
Reference: Koroljov's website (defunct)