本文分析日治時代臺灣地租是否過高。研究臺灣土地租佃制度的學者多認為戰前佃租過高，導致佃農生活貧困，阻礙農業的發展。根據總督府的調查，一九二七年及一九三七年水田地租佔收穫量的比率高達50％，旱田則為35％。至於為何地租如此之高，一般的研究皆認為是地主剝削所致，但是並未對此一主張進行分析。本文分別從土地對生產的貢獻與地主購地資金的機會成本兩個面向，檢視地租是否過高。初步結論歸納為三點。第一、地主十分關心收穫的狀況。為了提高出租地的收穫量，地主不只採行能夠激勵或不打擊佃農投資意願之地租訂立方式，也配合其他提高收穫量或其他不使收穫量降低的措施。第二、租率相當穩定。 水田地租率介於46％-51％，旱田地租率則介於23％-36％。第三、若以土地對生產的貢獻來定義適中的地租，則臺灣戰前地租過高的假設並不能成立。而若以地主購地出租的機會成本定義適中的地租，則地租過高的假設是否能成立視所採用的利率種類而定。此一結論顯示，我們不能毫無保留地支持戰前臺灣地租過高的假設。

　　　　　This paper analyzes whether or not Taiwan's farmland rent was too high during the Japanese colonial period. Most past studies on Taiwan's land tenure system claimed that the rent prevailing during the pre-war period was too high. Scholars generally believe thawt landlords' exploitation was the main factor to this high rent, however, none of them has ever made a systematic analysis for this assertion. This article tests whether or not the rent was too high both from the contribution of land to farm products and the opportunity costs of landlords' funds invested in land purchasing. Three main results are derived. First, landlords did care very much about the yield on their land. In order to raise tenants' incentives for investment and working attitude, two important arrangements were adopted in the tenure system. (1) A fixed rent system was chosen for land with a stable yield, while a share tenancy system was adopted on land with a very unstable yield. (2)Landlords also participated in land investment and lent working capital freely to tenants. Secondly, the rental rate was quite stable in the long run, and so landlords hared the fruits of their increased output and any loss from decreased output with their tenants. In the long run, landlords of farmfields suffered more risk than the tenants. Thirdly, the assertation that rent was too high cannot be accepted without any reservation. When we define the reasonable rent by the contribution of land to output, the assertaion does not hold. If the reasonable rent is definded by the opportunity cost of landlords'funds used in land purchasing, then whether or not the hypothesis holds depends on what kind of interest rate is used in the calculation. This finding shows that we cannot reservation.