Windy City Bulls (2017–2018) After going undrafted in the
2017 NBA draft, Johnson signed a training camp deal with the
Chicago Bulls. He was waived on October 14 as one of the final preseason cuts. On November 4, 2017, Johnson was included in opening night roster of the
Windy City Bulls. On March 24, 2018, the
Chicago Bulls announced that they had signed Johnson, but was waived on the next day. On October 20, 2018, the
Iowa Wolves announced that they had acquired the returning rights to Johnson and
Jarell Eddie from the
Windy City Bulls for the returning rights to
JaKarr Sampson and the draft rights to the No. 38 overall pick in the
2018 NBA G League Draft, Mike Amius.
Iowa Wolves (2019) On January 11, 2019, Johnson was added to
Iowa Wolves to their roster. In 21 games played for the Wolves, he averaged 8.7 points, 4.3 rebounds and 1 assist per game. On July 1, 2019, Johnson joined the
Indiana Pacers for the
2019 NBA Summer League.
Hapoel Holon (2019) On September 4, 2019, Johnson signed with
Hapoel Holon of the
Israeli Premier League for the 2019–20 season. On November 2, 2019, he parted ways with Holon after appearing in five games.
Second stint with Iowa Wolves (2019–2020) On November 20, 2019, the
Iowa Wolves announced that they had acquired returning right of Johnson. On January 5, 2021, Johnson signed with
Cherkaski Mavpy, but never played for them and on January 25, he was included in roster of the Iowa Wolves, but was later waived on February 13.
Motor City Cruise (2021–2023) In the
2021 NBA G League draft, Johnson was selected with the 8th pick by the
Motor City Cruise.
Nacional (2023) On March 27, 2023, Johnson signed with
Nacional of the
Liga Uruguaya de Básquetbol. Johnson help advance Nacional to the championship finals.
Taipei Mars (2023–2024) On September 14, 2023, Johnson joined the
Taipei Taishin Mars of the
T1 League. Jaylen Johnson helps his team to the championship finals. Jaylen Johnson scored 30 pts in loss against Boogie Cousins and The Taiwan Bears in June 2024. He was then drafted by team Bivouac with the Big 3.
Bivouac (2024) On May 28, 2024, Johnson was selected by Bivouac in 2024
Big3 draft.
Hapoel Hafia (2024) During summer 2024, he signed with
Hapoel Haifa of the
Israeli Basketball Premier League (ISBL).
Yalovaspor Basketbol (2024–2025) On October 22, 2024, he signed with
Yalovaspor Basketbol of the
Basketbol Süper Ligi (BSL).
Rain or Shine Elasto Painters (2026–present) On February 10, 2026, Johnson signed with the
Rain or Shine Elasto Painters of the
Philippine Basketball Association (PBA). ==Personal life==