Background: Diarrheal disease is the most common cause of illness and the second leadingrncause of child death in the world. The disease accounts for 4.3% of the total global diseasernburden; the burden being greatest in the developing world including Ethiopia. Even though therernwere studies that were done on childhood diarrhea in our country, they did not use analyticalrnstudy designs to explore associated factors of diarrheal morbidity.rnObjective: This study was intended to assess potential factors associated with diarrhealrnmorbidity among under-five children in Wolaita Soddo town, Southern Ethiopia.rnMethods: A community based case control study on sample population of 198 cases and 396rncontrols was conducted in Wolaita Soddo town, Southern Ethiopia, in 2010. Three kebeles basedrnon purposive sampling technique were selected to enumerate total cases (under-five childrenrnwith diarrhea) and their controls (under-five children with no diarrhea). For each case, tworncontrols were selected from neighboring households. From the total cases and controlsrnenumerated, 198 cases and 396 controls were selected randomly. Multiple logistic regressionrnanalysis was employed to evaluate independent effect of covariates on the diarrheal morbidity.rnResults: The odds of experiencing diarrheal morbidity was significantly higher among children:rnhaving fathers who were able to read and write (AOR=2.56; 95%CI=1.25, 5.25), having familiesrnwho perceived they were economically very poor (AOR=3.84; 95%CI=1.25, 11.82), havingrnfamilies without toilet facilities (AOR=13.45; 95%CI=3.58, 50.49), having families whoserncompound were observed to have faeces, having families who used well/spring/river as source ofrnwater, having mother/caretaker who did not wash at all critical hand washing times, havingrnmother/caretaker who did not know the three transmission modes of diarrheal morbidity.rnConclusion: The potential factors of diarrheal morbidity were concluded to be unavailability ofrntoilet facility, poor human waste management, and unsafe source of water, and poor personalrnhygiene, and lack of knowledge about transmission of diarrheal morbidity. Letting therncommunity have common toilet facilities and common safe source of drinking water, givingrnhealth education to households on human waste management, utilization of water, personalrnhygiene and transmission modes of diarrhea are recommended to alleviate the problem of underfivernchildren diarrheal morbidity.rnKeywords: Case control study, Diarrhea, Factors, Under-five children