Дисертаційну роботу присвячено поглибленню теоретико-методичних положень та розробленню практичних рекомендацій щодо реформування маркетингової інформаційної системи виробників побутових котлів в Україні в умовах цифрової економіки. Уточнено поняття «маркетингова інформація» та «маркетингова інформаційна система» в умовах цифрової економіки. Розроблено концептуальні положення архітектоніки маркетингової інформаційної системи підприємств в умовах цифрової економіки. Удосконалено методичні підходи до підвищення результативності функціонування маркетингової інформаційної системи підприємств. Побудовано модель оцінювання, що базується на теорії нечітких множин та нечіткої логіки і дозволяє виявляти напрями реформування відповідно до умов цифрової економіки. Розвинуто інструментарій реалізації заходів з підвищення результативності функціонування маркетингової інформаційної системи виробників побутових котлів, який, на відміну від існуючого, доповнений механізмом реформування, що враховує вимоги цифрової економіки до управління підприємством та містить: детермінанти інформаційних потреб підприємств; методи діагностики маркетингової інформаційної системи підприємств; цілі, принципи та інструменти реформування.^UThe dissertation is dedicated to deepening theoretical and methodical principles and providing practical recommendations for reforming the marketing information system of household boiler producers in Ukraine in the conditions of the digital economy. The essence of marketing information is cleared up and its role in the management of the enterprise in the digital economy is researched. As a result of the generalization of scientific developments, the definition is proposed that marketing information is a set of knowledge, information and communications about the external and internal environment of the company's operation, which are collected, generated and transferred to managers for making marketing management decisions, as well as formed and distributed to achieve marketing goals of the enterprise. According to the results of the scientific literature research using the management approach the definition of marketing information system is formulated as a constantly acting adaptive system of people's interconnection, technical and software and methodical techniques which is meant for collecting, processing, generating and distributing relevant, actual, timely and reliable information for marketing management of the enterprise and producing comprehensive marketing impact on the internal and external informational and communicative environment that ensures the achievement of strategic goals and solutions to operational tasks of the enterprise. The application of the functional process approach to the definition of the structure of the marketing information system. It is proposed to distinguish the subsystems of the marketing information system such as: 1) a monitoring system; 2) a system of marketing research; 3) a system for generating source information; 4) a system of storing data, information, methods and models; 5) a communication bus. The application of the structural and functional approach to the evaluation of the effectiveness of the marketing information system functioning is proposed. A system of indicators for the effective functioning of the marketing information system of household boiler producers has been built, which is connected with the new architectonics of the marketing information system. The model of the effectiveness evaluation of the subsystems of the marketing information system based on the theory of fuzzy sets and fuzzy logic is developed. It is proposed to use the index of the effectiveness of marketing activities as an indicator of the effectiveness of the marketing information system of the enterprise. The procedure for reforming the marketing information system is developed. It consists of the following stages: 1) the formulation of the reform goals; 2) the assessment of the current state of the marketing information system; 3) making a decision on the reform; 4) planning reform measures; 5) the realization of the reformation; 6) technical and functional control. A mechanism for reforming the marketing information system of the enterprise is developed in which diagnostic methods of the marketing information system are distinguished; the stages of decision making about the viability and choice of the direction of the reform are indicated; goals, principles and tools for reforming are defined; the result and the economic effect of the formation of marketing information system of the enterprise are analyzed. On the basis of the proposed procedure for reforming the marketing information system and the diagnostics of its current state, directions have been selected and measures for reforming the marketing information system of household boilers producer have been selected. The forecast values of the index of the effectiveness of the marketing activity of the company, which is planned to be obtained after the implementation of the planned activities in the functioning of the marketing information system, are developed. The method of estimating the enterprise market indicators, which is based on the content characteristics of the marketing activity of the enterprise and allows predicting the market effect of the marketing information system of the enterprise reforming, is improved.