Fish and fishery products are valuable sources of protein and essential micronutrients for balanced nutrition and good health. In Kenya, farmed fish is an integral nutrition, income earning and employment commodity for rural households. In 2010, the Government of Kenya initiated Economic stimulus program to encourage fish farming. Farmers took up the activity as a source of food and income. However, where adopted as business there were little returns (Kimathi et., al 2013). Farmers used diverse marketing channels that apparently posted different profit margins. Descriptive research design involving 147 fish farmers within Kirinyaga County, in 5 sub counties was used and data analyzed using multinomial logit model. It characterized market channels for fish farmers and analyzed the determinants of choice of marketing channel by farmers. The study identified 3 main channels; neighbors, direct market, traders and accounting for 49 percent, 29 percent, and 22 percent respectively. Gender of the household head, distance to market; marketing cost, land tenure, number of fish ponds owned, access to extension services, cost of marketing, membership to a fish farming group, access to inputs, household income, price of fish and type of fish reared had significant influence on farmers’ choice of market channel. Despite the government support, farmers faced challenges of predators, inadequate extension services and access to information. The conclusion is that county Governments and other stakeholders need to facilitate vibrant extension services and market support to the practicing farmers in their localities.