This paper aims to analyze the obligation to explain in veterinary medicine through case law analysis. As a result, there is clearly the obligation, except in emergency. Formally, the obligation is based on the principle of good faith as stipulated in Article 1, Paragraph 2 of the Civil Code. Substantially, the obligation to explain is based on the right of self-determination of the owners of pet animals or the right to property for other animals. Veterinarians must explain (1) the medical condition, (2) method of treatment, (3) risks of the chosen treatment, (4) details and risks of other treatments and their benefits and disadvantages, (5) prognosis, and (6) cost of each treatment. The court recognizes a causal relationship between the veterinarian’s breach of the obligation and the damage caused to the animal. However, a causal relationship should also be recognized between the violation of the obligation and the violation of the right to choose a treatment.