The study aimed to assess the antimicrobial efficacy of ethanolic extracts from Salvia officinalis leaves against Proteus mirabilis isolates, given the bacterium's significance in reoccurring cases of Urinary Tract Infections (UTIs) and resistance to conventional antibiotics. Sterile containers were used to obtain clean-catch urine samples from 20 hospitalized patients who are between the ages of 18-50 in Wukari. Spreadplate technique was used to culture samples on MacConkey agar for 24 hours at 32°C. Suspected colonies from a pure culture with a palesmooth appearance and urease-positive were subjected to molecular identification of the UreR gene using Polymerase Chain Reaction (PCR). Following the respective evaporation of the crude ethanolic extracts of the dried and fresh leaves, 2.0mg, 4.0mg, 6.0mg, 8.0mg, and 10.0mg were dissolved into 10ml dimethyl-sulfoxide respectively. Antimicrobial susceptibility test was conducted using the Agar-well diffusion technique. The zones of inhibition (ZIB) measured for the dried leaves ranged from 12-26mm for the various ethanolic concentrations 2.0mg10ml, 4.0mg-10ml, 6.0mg-10ml, 8.0mg-10ml, 10.0mg-10ml respectively, while the ZIB recorded for the fresh-leaves ranged from 10-24mm. No significant ZIB (≤3mm) was seen on the negative control which was the ethanol without extract. Ciprofloxacin 30μg was used as a positive control (≥29mm). Dried-leaf extracts of Salvia officinalis presented better antimicrobial activity on Proteus mirabilis compared to fresh-leaf extracts. The moisture content of fresh leaves was observed to favor microbial growth. Comparatively, both dried and fresh leaf extracts demonstrated moderate to strong antibacterial properties, falling within the effectiveness range of the positive control. Ultimately, this research successfully demonstrated the potential of Salvia officinalis as a medicinal plant in treating infections caused by Proteus mirabilis.