Navdeep Amarjeet Saini’s journey in cricket began at a young age, as he represented the Haryana cricket team at various age-group levels. His consistent performances at the domestic level caught the attention of the selectors, and he made his first-class debut for Haryana in the 2013-14 Ranji Trophy season.

Saini made his Twenty20 debut on 2 January 2016 in the 2015-2016 Syed Mushtaq Ali Trophy. In 2017, he was bought by the Delhi Daredevils team for the 2017 Indian Premiere League. In January 2018, he was bought by the Royal Challengers Bangalore in the 2018 IPL auction.

He was the leading wicket-taker for Delhi in the 2017-18 Ranji Trophy. He was also the leading wicket-taker for Delhi in the 2018-19 Vijay Hazare Trophy. In October 2018, he was named in India C’s squad for the 2018-19 Deodhar Trophy. The following month, he was named as one of the eight players to watch ahead of the 2018-19 Ranji Trophy.

He was selected for the Indian national team's tour of the West Indies in 2019. He also played ODI against the West Indies. Later in the year, he was selected in the Indian Team for the 2019 Cricket World Cup.

In February, he was brought by the Rajasthan Royals in the 2022 Indian Premier League auction. In July 2022, he signed a short-term deal with Kent to play up to three County Championship and five One-Day Cup matches in England. He made his debut against Warwickshire and took seven wickets.