A pick locking device for a plow pick that includes a pick shank inserted into a receptor box of a pick holder. The locking device may include a retaining pin and a deformable clamp element. The retaining pin may be forced through an opening on the pick holder into a locking groove extending in a shank insert direction along one side face of the shank. The clamp element may secure the retaining pin in a locked position, and may include a first leg and a second leg positioned at an angle to each other. The first leg may be inserted into a retainer in the pick shank and the second leg may be inserted into a locking recess on the retaining pin. The second leg may include a trunnion protruding from the first leg and an annular enclosed opening that extends to a rear of the first leg.