Objective: To assess the causative organisms and their sensitivity and resistance in presumed sepsis of neonates at tertiary care Hospital Study design and setting: This cross-sectional study was conducted at the Paediatric department of Liaquat University of Medical and Health Sciences Jamshoro/Hyderabad. Duration: Study duration was 6 months from November 2015 to April 2016 Data Collection: All neonates aged within 28 days, full-term or preterm babies with both male and female gender and clinical & some high-risk groups such as positive PROM history (prolonged rupture of membrane) less than 18 hours were included. Blood samples were taken from study subjects for blood culture with all aseptic precautions, inoculated in bottles having trypticase soy broth for aerobic bacterial isolation. Gram stain and standard biochemical techniques were applied to identify isolates. The screening of isolated pathogens was done for the 10 frequently used antibiotics susceptibility tests. Cases were categorized as EOS (early-onset-sepsis) if they were presented at hospital for <7 days of life and late onset sepsis if they were presented at or following the age of 7 days. The researcher registered the entire data on pre-planned proforma. Data entry and analysis was done via SPSS version 20.0. Results: Overall 332 patients were enrolled in this study. The patients mean age was 17.3 +/- 7 days. Males were found in majority 181 (54.5%). Most frequent organism isolated from blood was Klebsiella pneumoniae in (28.6%) cases, followed by E.coli 23.5%, staphylococcus aureus 19.6%, Listeria 13.3%, Streptococcal pneumonia 8.7%, Pseudomonas 3.9%, Proteus species 1.8% and Streptococcal viridians was seen in 0.6% cases, respectively. E. coli was found highly resistant to Ampicillin and highly sensitive to Amikacin; whereas Listeria was highly resistant to Cefuroxime and highly sensitive to Ciprofloxacin; Klebsiella species was highly resistant to Cefuroxime and highly sensitive to Ceftriaxone; Staph aureus species was highly resistant to Amikacin, Streptococcal pneumonia species were highly resistant to Amikacin and highly sensitive to Ciprofloxacin, Pseudomonas species were more resistant to Ampicillin & Gentamycin and highly sensitive to Cefotaxime; Proteus species were resistant to Ampicillin and Cefuroxime, more sensitive to Gentamycin, Cefotaxime, and Ciprofloxacin. Conclusion: It was conclude that Klebsiella pneumoniae was the most common organism isolated from blood 28.6%, followed by E. coli 23.4% and staphylococcus aureus in 19.5% cases. Most common sensitive antibiotics were Amikacin, gentamycin, and ciprofloxacin, gentamycin, Cefotaxime, Amikacin and ceftriaxone.