The invention provides a thick-gauge steel plate with excellent low-temperature aging performance, and a manufacturing method thereof. The thick-gauge steel plate with excellent low-temperature aging performance is composed of the chemical components of, by weight: no more than 0.20wt% of C, no more than 0.50wt% of Si, no more than 1.60wt% of Mn, 0.020-0.050wt% of Nb, 0.010-0.050wt% of Ti, 0.015-0.050wt% of Als, no more than 0.015wt% of P, no more than 0.012wt% of S, and balance of Fe and unavoidable impurities. Through low-carbon micro-alloying, and through the controlling over rolling, cooling, and normalizing treatment, the steel plate has good low-temperature aging impact performance. The thick-gauge steel plate provided by the invention satisfies -50 DEG C impact work requirements before and after aging, and has uniform tissue and excellent properties. With the steel plate, an ultrasonic flaw detection requirement is satisfied, and the requirement for a structural steel plate for an offshore oil platform is satisfied.