The Tifalmin and Nong River copper-gold porphyry/skarn districts are located in the Star Mountain near the Papua New Guinea border, approximately 35km NE of the Ok Tedi porphyry copper deposit (Figure 1). The districts cover two clusters of temporally related diorites associated with copper-gold porphyry and skarn mineralisation. This paper summarizes some of the recent work carried out by the former Star Mountains Joint Venture partners (Highlands Pacific and Anglo American) aimed at better understanding the relationships between the mineralised and unmineralised intrusions and the structural controls on the mineralisation. CITATION: Queen, L D and Ulaiwi, L, 2019. Update on structural controls and timing of copper-gold porphyry and skarn mineralisation in the Tifalmin and Nong River Districts, Star Mountains, Papua New Guinea, in Proceedings PACRIM 2019, pp 192195 (The Australasian Institute of Mining and Metallurgy: Melbourne).