Background Cervicogenic headache (CEH) is often refractory to monotherapies, and treatment strategies combining neuromodulation and myofascial interventions may offer additional benefits. This study evaluated the clinical effectiveness of ultrasound-guided C2 dorsal root ganglion (DRG) pulsed radiofrequency (PRF) combined with suboccipital myofascial plane block (SMPB) in subjects with CEH. Methods This retrospective study analyzed 67 CEH subjects treated with PRF alone ( n = 28) or combined PRF + SMPB therapy ( n = 39). Pain intensity (VAS), headache frequency and duration, Short-Form McGill Pain Questionnaire (SF-MPQ), and Neck Disability Index (NDI) were assessed at baseline, 1 week, 1 month, 3 months, and 6 months. Results The combined treatment produced significantly greater improvement in pain outcomes. At 3 months, VAS scores were 2.09 ± 1.38 in the PRF + SMPB group vs. 3.55 ± 1.11 in the PRF group (between-group difference Δ = −1.46; 95% CI −2.06 to −0.86; p < 0.001). Superior improvements were also observed in headache frequency, headache duration, SF-MPQ, and NDI at multiple timepoints. All subjects completed follow-up (attrition rate 0%), and no complications or minor adverse events were reported. Conclusions Ultrasound-guided C2 DRG PRF combined with SMPB demonstrated greater reductions in pain and disability than PRF alone in CEH. These findings provide preliminary, hypothesis-generating evidence supporting the feasibility and clinical utility of this multimodal approach. Prospective randomized trials with longer follow-up are warranted.