Acute low back pain is a common cause of pain in the majority of the adult population. Facet joints are a potential source of pain in low back pain (LBP) and its prevalence increases with age. Our case report is about a 34-year-old male patient who came with chief complaints of chronic low back ache, more on the left side, insidious in onset, non-radiating not associated with tingling or numbness. Pain aggravates on walking, sitting to standing posture, and left side movements. His Numerical rating scale (NRS) was 7 and the Verbal rating scale (VRS) was moderate. On palpation patient had left para median tenderness more at L5-S1 area. The Lasegue straight leg raising test and flexion, abduction, external rotation (FABER) were also negative. We decided to proceed with diagnostic block of left L5-S1 facet joint with 1ml 0f 1% lignocaine and our patient had significant pain relief of about 80%.