<p><b>OBJECTIVE: </b>-6 and -3 long-chain PUFA play opposing roles in inflammation, anxiety and nociception, all of which are closely associated with chronic pain. We hypothesised that diets high in -6 arachidonic acid (C20:4-6, AA) and low in combined -3 EPA (C20:5-3, EPA) and DHA (C22:6-3, DHA) would be associated with higher odds of painful temporomandibular disorder (TMD).</p><p><b>DESIGN: </b>We analysed baseline data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL). Two 24-h dietary recall surveys quantified intake of long-chain -6 and -3 PUFA along with their precursors, linoleic acid (C18:2-6, LA) and alpha linolenic acid (C18:3-3, ALA), respectively. -3 PUFA supplementation was quantified. Interviewer-administered questions assessed TMD. Survey multiple logistic regression estimated covariate-adjusted OR and 95 % confidence limits (CL) for associations between PUFA and TMD.</p><p><b>SETTING: </b>From 2008 to 2011, HCHS/SOL recruited 16 415 adults of Hispanic/Latino backgrounds (Cuban, Puerto Rican, Dominican, Mexican, Central/South American), through field centres located in Miami, FL; San Diego CA; Chicago, IL; and the Bronx, NY.</p><p><b>PARTICIPANTS: </b>13 870 participants with non-missing data.</p><p><b>RESULTS: </b>In analysis adjusted for covariates, each sd increase in dietary intake of C20:4-6, AA was associated with 12 % higher odds of TMD (OR = 1·12, CL: 1·01, 1·24). Although the dietary intake of combined long-chain C20:5-3, EPA and C22:6-3 DHA was not associated with TMD, each sd increase in -3 dietary supplement was associated with lower odds of TMD.</p><p><b>CONCLUSIONS: </b>A diet rich in C20:4-6, AA was associated with higher odds of painful TMD.</p>