BACKGROUND Important public health and clinical issues remain unanswered concerning disease-related knowledge and caregiving experiences in dementia. The aim of this study is to describe these dimensions in Portuguese clinical settings and analyze the link between knowledge and burden, and also between knowledge and positive caregiving experiences. METHODS We studied a non-randomized sample of 116 caregivers of outpatients with ICD10-DCR diagnosis of dementia. Comprehensive assessments included Dementia Knowledge Questionnaire (DKQ), Zarit Burden Interview (ZBI), Caregiving Activity Survey (CAS), Positive Aspects of Caregiving (PAC) and General Health Questionnaire-12 (GHQ). Portuguese translations for DKQ, ZBI and PAC scales had been developed; validity aspects were documented, as well as test-retest reliability coefficients for ZBI (ICC = 0.93) and PAC (ICC = 0.85). RESULTS Most caregivers were close relatives, female and living with the patient. Although positive aspects of care were reported, burden and distress levels were moderate to high. Knowledge needs were not striking. Distress was moderately correlated to burden, but no associations were found between caregivers' knowledge and ZBI, PAC or GHQ. DKQ scores did not predict PAC nor ZBI scores. A relationship was found between ZBI, as dependent variable, and PAC, GHQ and CAS. CONCLUSIONS A large proportion of caregivers in this sample, albeit informed about dementia, were at risk of high burden and distress. Knowledge about dementia may not be protective of burden per se, nor did it influence positive aspects of caregiving.