After his release from the Phillies, Kline retired and began coaching in the Giants instructional leagues.

On December 17, 2008, he was announced as the pitching coach for the Single-A Augusta GreenJackets.

On May 10, 2011, Kline was suspended after he head-butted an umpire.
 He was later suspended for 15 days and fined $500 for the incident.

On January 26, 2012, he was announced as the pitching coach for the Class A Advanced San Jose Giants.

Then, in the World Baseball Classic Qualifier, which took place in Taiwan from November 15 to 18, 2012, Kline was the pitching coach of team New Zealand.

In more recent years, Kline was the pitching coach for the Richmond Flying Squirrels, a position he was named to for the 2015 season, the Double-A affiliate of the San Francisco Giants in the Eastern League, then was later named pitching coach with their Triple-A affiliate, the Sacramento River Cats of the Pacific Coast League, in 2017 and is with that club again for the 2018 season.
After his release from the Phillies, Kline retired and began coaching in the Giants instructional leagues.
On December 17, 2008, he was announced as the pitching coach for the Single-A Augusta GreenJackets.
On May 10, 2011, Kline was suspended after he head-butted an umpire.  He was later suspended for 15 days and fined $500 for the incident.
On January 26, 2012, he was announced as the pitching coach for the Class A Advanced San Jose Giants.
Then, in the World Baseball Classic Qualifier, which took place in Taiwan from November 15 to 18, 2012, Kline was the pitching coach of team New Zealand.
In more recent years, Kline was the pitching coach for the Richmond Flying Squirrels, a position he was named to for the 2015 season, the Double-A affiliate of the San Francisco Giants in the Eastern League, then was later named pitching coach with their Triple-A affiliate, the Sacramento River Cats of the Pacific Coast League, in 2017 and is with that club again for the 2018 season.
Steve Kline (left-handed pitcher)