It is important to understand how catfish farmers use mobile phones in their business activities to enhance the adoption and utilization of mobile phones in fish farming. The study assessed catfish farmers' use of mobile phones for business activities at Uteh fish farming cluster, Edo State, Nigeria. The study examined the business activities mobile phones are used for, the fish farmers' perceived competence, and the challenges faced in using their mobile phones. Data were collected from 71 catfish farmers at the Uteh fish farming cluster through convenience sampling, using a structured interview schedule. Frequency counts, Percentages, means, and correlation were used to analyze the data. The results show the average age of the farmers to be 44 years, farmers were mostly (71.8%) male, and about 90% of them were married. All (100%) of the fish farmers indicated that they used their mobile phones for basic business activities like receiving calls and sending SMS, using social media apps such as WhatsApp, contacting buyers, and taking pictures for business. The Catfish farmers were competent in the use of mobile phones except in obtaining loans (mean = 2.42), using aquaculture apps (mean = 2.62), and checking weather forecasts (mean = 3.62). However, the use of mobile phones by the catfish farmers was constrained by poor network coverage.