[3] Shahidul Karim joined the judicial branch of the Bangladesh Civil Service on 20 April 1983 as a munsif.
[3] On 20 October 2011, Shahidul Karim was made an additional judge of the High Court Division.
[3][4] In November 2017, Shahidul Karim and Justice M Enayetur Rahim said no one was above prosecution in a hearing on a letter the administrative branch of the Bangladesh Supreme Court to the Anti Corruption Commission which suggested that the commission did not have the authority to investigate retired Supreme Court judge Md Joynul Abedin.
[5][6] In March 2018, Shahidul Karim and Justice M Enayetur Rahim asked the government to explain why the jail sentence of former prime minister Khaleda Zia in the Zia Charitable Trust corruption case should not be enhanced.
[9] Shahidul Karim and Justice Md Mostafizur Rahman are hearing the July 2016 Dhaka attack case.