Niklas Tarvajärvi

Jokerit

Tarvajärvi started his career at FC Jokerit in Finland's Veikkausliiga. During the 2001–2004 seasons, he represented the team in 39 matches and scored 11 goals.

MyPa

After FC Jokerit was sold to rivals HJK Helsinki in March 2004 and renamed to Klubi-04, Tarvajarvi transferred to MyPa. In the next two seasons, he made 37 appearances and 3 goals.

Heerenveen

In the summer of 2005, he moved to Heerenveen. Between 2005 and 2009, he made 30 appearances for the team and scored four goals. He also spent time on loan in De Graafschap and Vitesse Arnhem.

Neuchâtel Xamax

After almost four years in the Netherlands, Tarvajarvi joined Neuchâtel Xamax in February 2009 for a transfer fee of €500,000.

Karlsruher SC

He then signed a two-year contract on 21 July 2009 with Karlsruher SC.

Go Ahead Eagles

After his contract in Karlsruher SC ended he transferred to Dutch Eerste Divisie side Go Ahead Eagles.

RoPS

In April 2013, it was reported that Tarvajärvi had signed a contract with Veikkausliiga team RoPS. He decided to leave the team after only 10 appearances.

Tarvajärvi debuted in the Finland national team on 12 March 2005, coming on as a substitute against Kuwait in a friendly match.

Since his retirement, he has worked as a youth coach for SC Heerenveen, and as a head coach for VV Heerenveen. On 24 May 2024, Tarvajärvi was named the head coach of SC Heerenveen (women).

His grandfather was a TV and radiojournalist Niilo Tarvajärvi. His son Niilo Tarvajärvi is also a footballer, playing for Ajax U16 youth academy team.