King began the 2012–13 season by failing to qualify for three of the first four ranking events.&lt;ref name="2012/13"&gt;&lt;/ref&gt; The one he did reach was the Shanghai Masters, where he beat Zhao Xintong 5–3 in the wildcard round and local favourite Ding Junhui 5–4 in the first round, having trailed 0–3. He lost 3–5 to Shaun Murphy in the following round. King saw off Mark Williams 6–3 in the first round of the 2012 UK Championship, before surrendering a 3–0 lead against 17-year-old Luca Brecel to lose 4–6. He also reached the second round of the German Masters by whitewashing Stephen Maguire 5–0, but then lost in a deciding frame to Matthew Stevens. King failed to qualify for the World Open and lost in the first round of the Welsh Open and China Open. He faced Mark Allen in the opening round of the World Snooker Championship and produced a big shock by fighting back from 6–8 down to produce his best snooker at the end of the match in a 10–8 win. He raced into a 6–2 lead in the first session of his second round match against Ding Junhui, before falling 7–9 behind in the next session and ultimately lost 9–13. King ended the season ranked world number 29.