Parasites remain a major threat to the health and welfare of animals all over the globe. The impact is greater in Africa in general and in Ethiopia in particular due to the availability of a wide range of agro-ecological factors suitable for diversified hosts and types of helminthes. Therefore, the objectives of the experiment were to estimate the infestation level of parasites, to know the associated risk factors and to identify the presence antihelmentic drug resistance. In the present study both fecal sedimentation and floatation techniques were used for trematode and nematode eggs identification, respectively. As well as two types of drugs namely Albenda-qk 600 mg and Flukash Sheep (Oxyclozanide 340 mg) were used to distinguish the existence of antihelmentic drug resistance and STATA (version 13) statistical software used to analysis the associated risk factors. As the study result indicated the prevalence of nematode and trematode during pre-treatment period were 66% and 29%, respectively, whereas the prevalence of nematode and trematode during post-treatment period 7% and 3%, respectively. As multivariable logistic regression model analysis result showed that age and stage of deworming were statistically significant association with both nematode and trematode positivity (P < 0.05). Even though, there was statistically significant variation (P < 0.05) of both nematode and trematode parasite positivity between pre-treatment and post-treatment period there were still small group of sheep flocks have been developed resistance. Therefore, to prevent further the development of anthelmintic drug resistance intervention activities such as strategic and integrated antihelmentic drug application, avoidance of under dosage of animal treatment and application of antihelmetic drugs rotation and anthelmintic efficacy test should also be practiced regularly.