臺灣在2015年高齡人口（65歲以上）比例超過12.5%，依照國家發展委員會的2016年人口推估，預計將於2018年正式邁入高齡社會（高齡人口比例14%），2026年更突破20%的門檻，人口老化速度持續加快。因為身體機能隨年齡增長等因素逐漸老化，高齡人口的就醫需求通常也較多，包括就醫金額、就醫次數，根據中央健康保險署2014年統計，高齡人口比例約為12.0%，但其醫療費用卻佔總費用37.6%。因此本文以探討高齡人口就醫特性為目標，透過高齡人口就醫行為去了解醫療現況，並評估因老化而引發的醫療資源。 本文以高齡人口特性及就醫需求為研究方向，探討近十年高齡人口就醫需求的基本特性，如：醫療使用率、平均就醫次數及平均醫療費用。接著以高齡人口就醫選擇集中度做為出發點，計算各疾病下的就醫集中程度，探討是否高齡人口會隨著不同疾病而有不同的就醫行為。研究結果顯示年紀越大的高齡人口，醫療使用率反而下降，但平均總醫療花費隨著年齡增加亦跟著上升；另外在不同的疾病下會有不同的就醫行為，當就醫地選擇越一致其死亡率也越低。計算依據為全民健康保險資料庫2005年百萬高齡人口抽樣檔，包括承保資料檔(ID)、門診處方及治療明細檔(CD)、住院醫療費用清單明細檔(DD)，以六十五歲以上高齡人口為研究對象，探討其醫療利用行為及就醫習性。 / The population aging is speeding up in Taiwan. The elderly population (65 years and older) is more than 12.5% in 2015 and, according to the population projection of National Development Council, it is expected to reach 14% and 20% in 2017 and 2026, respectively. The elderly usually require more medical attention, partly due to the fact that the human organs degenerate with time. For example, in 2014, the proportion of elderly is about 12.0% and they account for 37.6% of total medical expenditure (Source: National Health Insurance Administration). Taiwan’s total medical expenditure will continue to grow and we need to understand the medical needs of Taiwan’s elderly, in order to cope with the need of aging society. Therefore, we use the data from the National Health Insurance Research Database (NHIRD) to explore the medical needs and behaviors of receiving medical care of Taiwan’s elderly. The dataset used in this study is a sample (one million people aged 65 and beyond, about 46% of total population) of Taiwan’s elderly and the dataset contains the Registry for beneficiaries (ID), outpatient visits (CD), and inpatient admissions (DD). Our analyses show that almost all elderly have at least one medical visit annually and their diseases are more diverse than those of younger generations. Also, the elderly have larger inertia in medical visits and, for example, the proportion of choosing the same medical institution is higher. The results of this study can serve as a reference to future policy planning and resource allocation for the elderly.