Jacek JANISZEWSKI was born in Warsaw in 1969 and, following his training in horn, studied voice at the Fryderyk Chopin Academy of Music in Warsaw with Roman Węgrzyn. During his studies he participated in several master classes conducted by the noted Polish tenor Ryszard Karczykowski and by the Bulgarian teacher Rusko Ruskov in Sofia. Since 1998 he has worked with Kurt Moll and since 2001 with Franz Hawlata.

Jacek Janiszewski won first prizes and special awards at international vocal competitions, for example, in Warsaw (3rd Stanisław Moniuszko Vocal Competition 1998) and Vienna (Belvedere Singing Competition 1999). He was a finalist at Plácido Domingo's Operalia Contest 1997 in Tokyo and at the New Voices Singing Competition 1997 in Gütersloh.

Beginning in 1997 he was engaged at the Flensburg Regional Theater, appearing in roles such as Sarastro in Die Zauberflöte, the Commendatore in Don Giovanni, Don Alfonso in Così fan tutte, Don Basilio in Il barbiere di Siviglia, Sparafucile in Rigoletto, Banco in Macbeth, Pimen in Boris Godunov, Daland in Der fliegende Holländer and Emperor Altoum in Busoni's Turandot.

He continues to make guest appearances in his native country, for example, at the  Warsaw State Opera in the role of Zbigniew in The Haunted Manor by Stanisław Moniuszko,  Leporello in Mozart's Don Giovanni, Colline in La Boheme by G. Puccini  and at the side of José Cura as Zuniga in Carmen, or at the Cracow Opera Theater as Sarastro and Ramfis in Aida.

Since 2003 Jacek Janiszewski has appeared at the Hanover State Theater as Osmin in Mozart's Die Entführung aus dem Serail, Ferrando in Il trovatore and Ercole in Cavalli's Giasone.

Jacek Janiszewski is a regular guest at the Chiemgau Opera Summer and sang the roles of Sarastro, Leporello, Colline in La bohème and Bartolo in Le nozze di Figaro with great success. In summer 2004 he appeared as Osmin in Die Entführung aus dem Serail and Don Fernando in Ludwig van Beethoven's Fidelio, and in summer 2007 as Basilio in Gioachino Rossini's Barbier von Sevilla.

His busy concert career has taken him to numerous cities throughout Germany and Poland. He sang Beethoven's Mass in C major and the Verdi Requiem with the Warsaw National Philharmonic Orchestra, conducted by Kazimierz Kord. He was a soloist in Haydn's The Creation and The Seasons and Edward Elgar's The Dream of Gerontius with the Schleswig-Holstein Symphony Orchestra, conducted by Matthias Janz, as well as  Beethoven's Ninth Symphony with the Munich Symphony Orchestra in the Herkules Saal (2002). During the summer of 2002 he appeared at the Richard Strauss Festival in Garmisch-Partenkirchen, singing the role of Peneios in Daphne (conducted by Pinkas Steinberg, with Francisco Araiza and Birgit Remmert).

Since December 2005 he has been a member of the ensemble at the Bielefeld Municipal Theater and was heard as Osmin in Die Entführung aus dem Serail, Thibaut D'Arc in Tchaikovsky's The Maid of Orleans and King Arkel in Claude Debussy's Pelléas et Mélisande.
In season 2006/2007 he sang the roles of Bartolo in Le Nozze de Figaro by W.A.Mozart, Don Belflore in Le Toréador by Adolphe Adam, Ramfis in Aida by G. Verdi and in Der Sturm von Zdenek Fibich.
In season 2007/2008 he had sung two great roles: Walter in G. Verdi's Luisa Miller and King Marke in Tristan und Isolde by R. Wagner.

In market place two CD-recordings are available: Rothschild's violin by Fleishmann with Royal Liverpool Philharmonic Orchestra (Conductor: V.Petrenko) and Siegfried Wagner's Rainulf & Adelasia (Conductor: Werner Andreas Albert).

Since May 2006 Jacek Janiszewski is a regular guest in the rock oratorio TU ES PETRUS by Piotr Rubik. Presently one of the most successfull music projects in the polish charts with the usually-sold number of music CD/DVDs.

In season 2009/2010 he is booked as Leporello and Doktor Grenvil at state opera Warschau, as Baculus in Wildschütz from Albert Lortzing in Bielefeld and as Kaiser Altoum in Busoni's Turandot in Teatro de la Maestranza in Sevilla.

In august 2010 he will have to be heared as Stolnik in operatic concert from Moniuszko's Halka at the Schleswig-Holstein Musik Festival.