Objective To investigate the microbial contamination status of ultrasonic coupling gel and probe surfaces in hospital, and to provide a scientific basis for the prevention and control of infections related to ultrasonic examinations. Methods A cluster sampling combined with convenience sampling method was adopted. In March 2025, three departments in Suining Central Hospital with high-frequency ultrasound examinations, namely the Physical Examination Center, Ultrasonic Imaging Department and Emergency Department of the hospital, were selected for sampling for 2 consecutive weeks, which covered the morning and afternoon of working days from Monday to Friday. Microbial culture and counting were conducted on the ultrasound probes for intact skin contact, which were standby after routine cleaning and disinfection in the departments, as well as the in-use ultrasonic coupling gel. Meanwhile, the dominant bacterial strains cultured were identified. Results A total of 168 samples of standby ultrasonic probes and 129 samples of in-use ultrasonic coupling gel were collected. The total colony count qualified rate of standby ultrasonic probes was 44.64% (75/168), with 58.67% (44/75) in the Physical Examination Center, 57.14% (8/14) in the Emergency Department, and 29.11% (23/79) in the Ultrasonic Imaging Department. There was a statistically significant difference in the qualified rate of probes among different departments (P<0.05). The total colony count qualified rate of in-use ultrasonic coupling gel samples was 29.46% (38/129), including 50.00% (3/6) in the Emergency Department, 33.33% (15/45) in the Physical Examination Center, and 25.64% (20/78) in the Ultrasonic Imaging Department. There was no statistically significant difference in the qualified rate of coupling gel among different departments (P>0.05). Bacterial species identification showed that the types of contaminating bacteria in in-use ultrasonic coupling gel and standby ultrasonic probes were similar, mainly Burkholderia pyrrocinia accounting for 65.76% (121/184), Burkholderia stabilis accounting for 28.80% (53/184). Pseudomonas aeruginosa, Staphylococcus aureus, and mold were not detected. Conclusions The standby ultrasonic probes and in-use ultrasonic coupling gel in the hospital have microbial contamination, with Burkholderia cepacia complex as the main contaminating bacteria. This poses a risk of nosocomial infection and requires further strengthening of management.