The previous studies conducted in Ethiopia have mainly concentrated on the adoption of tef and wheat crops, along with complementary inputs. However, there has been a notable gap in research when it comes to examining the factors that influence the demand for certified seeds in the country. The study aimed to assess the factors that influence farmers' decisions to purchase certified seeds and the quantity of certified seeds purchased by tef and wheat farmers. Data were collected from 186 randomly selected sample farmers using a multistage sampling approach. A double hurdle model was used to analyze the data, considering that the decisions to participate in certified seed purchase and the quantity of purchased are influenced by different factors. The results showed that household size, tef farming experience, and proximity to cooperative office, age, and land size had a significant effect on the likelihood of purchasing certified tef seeds. Education level, distance to extension office, certified wheat seed price, and extension contacts were found to significantly influenced the decision to purchase certified wheat seeds. Furthermore, education level, land size, certified tef and wheat seed price, livestock ownership were significantly influenced both quantity of certified tef and wheat seeds purchased. In conclusion, enhancing farmers' skills, ensuring local seed availability through collective actions, and implementing a seed price subsidy program could enhance crop productivity for farmers with limited resources. The study suggests that farmers' seed producer cooperatives and private seed suppliers should be encouraged to increase their involvement in producing certified self-pollinated seeds.