2003-04: Erik Johnson played 31 games for the Academy of Holy Angels in Minnesota. He tallied 34 points (13 goals, 21 assists), helping the team go 25-5-1 while winning the Conference Championship. He attended the USA Hockey Select 15 camp.
2004-05: Johnson debuted for the USNTDP. He played 42 games for the U-17 Team and 15 games for the U-18 Team. In 57 total games he tallied 26 points (11 goals, 15 assists). His 26 points were the most for a defensemen playing for the USNTDP. He also compiled 26 PIM. Johnson helped the USA win the Four Nations Cup with four points in four games (one goal, 3 assists) and was also a member of the gold medal winning Team USA at the 2005 International Ice Hockey Federation World U-18 Championships.
2005-06: Johnson had a strong 2005-06 season for the USNTDP U-18 Team. In 47 games he tallied 49 points (16 points, 33 assists). He led all defensemen in goals, assists, points, and PIM with 88. His 1.04 points per game was second best on the team and best for a defenseman. Johnson played in 20 of 22 games against NCAA teams. He led all defensemen in points against the NCAA teams with 15 (six goals, nine assists). He was a member of Team USA at the World Junior Hockey Championships and played a strong tournament, finishing in the top 10 highest scoring defensemen with four points (one goal, three assists).
2006-07: Johnson made his NCAA debut with the University of Minnesota. His play was solid throughout, and he helped make the Golden Gophers one of the top teams in the country. His superb two-way play saw him record 24 points in 41 games, as well as contribute steady defense. Johnson was Team USA's top defenseman at the World Juniors, leading his squad to a bronze medal.
Johnson is projected to be a top-pairing two-way defenseman who can rush the puck up ice with his excellent stickhandling and passing skills as well as his smooth skating stride. He is reliable in his own zone, using his 6’4 frame to knock forwards off the puck and keep traffic clear around his own goal.