Background: Pain after lumbar spine surgery is often difficult to control in the post-operative period. The ultrasound-guided erector spinae plane block (ESP) is relatively safe, simple, and there have been no a lot of controlled studies to evaluating its Efficacy. Objective: To compare the effect of Bupivacaine alone versus Bupivacaine plus Fentanyl, and Bupivacaine plus Dexamethasone in ultrasound-guided erector spinae plane block in lumbar spine surgeries. Patients and Methods: Ninety patients of both sexes admitted for lumbar surgery. They were randomly allocated into three equal  groups: Group A: Control group received bilateral ultrasound-guided erector spinae plane block (bupivacaine alone), group B  received bilateral ultrasound-guided ESPB (Bupivacaine + fentanyl) and group C  received bilateral ultrasound-guided ESPB (Bupivacaine + Dexamethasone), The following parameters were assessed in the three groups: Heart rate (HR), mean arterial blood pressure (MAP), oxygen saturation (SpO2), end-tidal CO2, total narcotic need in first 24 hours, visual analog score (VAS), total amount of opioid in first 24 hours, postoperative nausea and vomiting, and duration of pain relief postoperatively. This study was done at Al-Azhar University Hospitals after approval of the medical ethical committee, from August 2020 till January 2021. Results: This study showed that the addition of dexamethasone to bupivacaine prolonged the time of block and analgesia duration longer than fentanyl. Also, the addition of fentanyl to bupivacaine prolonged the time of block and analgesia duration longer than bupivacaine alone. Conclusion: Bilateral ultrasound-guided erector spinae plane block in lumbar spine surgeries is one of the most advantageous adjuvant blocks for improving post-operative pain, and a decrease in opioid side effects. The addition of additive to bupivacaine-like fentanyl, and dexamethasone enhanced the duration of post-operative analgesia till the analgesia request and leads to reduction in pain score in 1st 24 hours post-operative.