日本央行行長植田和男在2025年12月1日對外釋放明確的加息訊號，顯示央行極可能在12月19日的政策會議上正式啟動升息。這一舉動是日本自長期寬鬆政策以來的重要轉折，背後反映的，是日本正面臨愈來愈沉重的通膨壓力，以及日元匯率持續走弱所帶來的經濟負擔。植田的言論使市場瞬間提升對加息的預期，不僅讓日元立即出現反彈，也引發債市與股市的劇烈波動。

此次釋出加息訊號的核心原因來自通膨與匯率的雙重壓力。日本10月核心消費者物價指數再次同比上漲3.0%，至今已連續50個月高於2%的政策目標。這種長期且頑固的通膨並非只來自國際能源與原物料價格上升等輸入性因素，國內薪資在2024年亦出現罕見的同步成長，平均薪資增幅達3.7%，顯示內需通膨壓力正在提升。與此同時，日元在 2025年內對美元累計貶值約 5%，甚至突破155的重要關卡。日元疲弱意味著日本進口能源、食品、原料的成本大幅上揚，對企業與家庭形成沉重負擔，也促使政府與央行開始支持升息，藉此改善利差、減緩匯率下滑。

植田的談話立即在金融市場掀起連鎖反應。外匯市場率先反應，美元兌日元從156.18的高位迅速回落至155.60，顯示市場提高短期日元升值的押注。然而，由於日本經濟長期結構問題仍在，如勞動力不足、企業競爭力下降與人口老化嚴重，市場普遍認為日元的回升空間仍受限。債券市場則受到更直接的衝擊，10年期日本國債收益率攀升至1.85%，創下2008年以來的最高水平；2年期收益率首次突破1%；30年期長天期國債也上升至 3.385%。大量的債券拋售反映投資人擔憂日本將進入新一輪升息循環，使政府高額債務的負擔更加沉重。

日本股市同樣受到波動，日經指數曾一度下跌近2%。投資者擔心升息將使企業融資成本提高，加上外資大量利用低息日元進行套息交易，一旦升息預期持續發酵，這些資金可能迅速撤離，導致平倉潮並加劇市場震盪。

這一次日本可能升息的行動，更被視為牽動全球金融市場的關鍵變數。全球規模估計達1至3兆美元的日元套息交易，一旦面臨大規模平倉，不僅會推高日元匯率，更可能引發美國國債、科技股與新興市場資產的連鎖式拋售，形成全球性資金位移。由於美聯儲在 2025年已有降息的政策壓力，一旦日美利差縮小，市場波動將更為劇烈。

目前市場預期日本在12月加息的機率已升至76%，並可能將政策利率從0.5%上調至0.75%。然而，日本政府債務規模高達GDP的230%，這意味著過快或過急的加息將大幅增加政府利息支出，使財政承壓。因此，市場普遍認為日本央行即便真的啟動升息，也將採取極為溫和且漸進的路線。

然而，對於升息是否能真正扭轉日元長期走弱的趨勢，市場存在明顯的分歧。有部分分析認為，日本經濟的結構性弱勢並未改善，單靠溫和升息不足以支撐匯率，甚至可能使日元在短暫反彈後再度走貶。另一派則認為，若美聯儲正式進入降息周期，而日本同時升息，日美利差將急速縮小，日元將迎來強力反彈，甚至可能改寫近年來的貶值趨勢。不過，政策的不確定性與市場預期本身的反覆，仍可能帶來更多的波動風險。

整體而言，日本央行此次釋放的加息訊號，不僅象徵日本貨幣政策重大轉向，也構成全球金融市場在年底前最受關注的變數之一。無論升息是否成真，此事件已經凸顯日本正在努力平衡通膨、匯率與債務三者之間的艱難拉鋸，而這場政策博弈的結果，將深刻影響未來亞洲與全球的市場走勢。

On December 1, 2025, Bank of Japan Governor Kazuo Ueda sent a clear signal that the central bank is preparing to raise interest rates, implying that a rate hike may be announced at the upcoming December 19 policy meeting. This marks a significant shift away from Japan’s long-standing ultra-loose monetary stance. The message reflects the mounting inflationary pressures Japan is facing, as well as the economic strain caused by the yen’s continued depreciation. Ueda’s remarks immediately heightened market expectations of a rate hike, prompting the yen to rebound and triggering volatility in both the bond and equity markets.

The principal catalyst for this potential rate increase lies in the combination of persistent inflation and a weakening currency. Core CPI in Japan rose 3.0% year-on-year in October, marking the 50th consecutive month above the Bank of Japan’s 2% target. This prolonged and stubborn inflation is being driven not only by imported cost pressures such as higher energy and raw material prices, but also by an unusually strong rise in domestic wages, which grew an average of 3.7% in 2024. Meanwhile, the yen depreciated roughly 5% against the U.S. dollar in 2025 and even breached the psychologically important 155 level. The weak yen has sharply increased the cost of importing energy, food, and raw materials, placing a heavy burden on households and businesses. These factors have pushed both the government and the central bank toward supporting rate hikes to narrow the interest rate differential and stabilize the currency.

Financial markets reacted immediately following Ueda’s comments. The foreign exchange market was the first to move, with the USD/JPY falling from 156.18 to 155.60, reflecting short-term bullish expectations for the yen. However, due to Japan’s structural economic problems—such as labor shortages, declining corporate competitiveness, and severe population aging—analysts generally believe that the yen’s room for long-term appreciation is limited. The bond market experienced even sharper reactions: the 10-year Japanese government bond yield surged to 1.85%, the highest since 2008; the 2-year yield climbed above 1% for the first time; and the 30-year yield rose to 3.385%. These moves reflect increased selling pressure as investors worry that Japan may be entering a new tightening cycle that could significantly raise debt-servicing costs in a country burdened with massive public debt.

Japan’s equity market was also affected, with the Nikkei index at one point dropping nearly 2%. Investors grew concerned that higher interest rates would raise corporate borrowing costs. Additionally, foreign investors—who have long used the yen for large-scale carry trades—now face the risk of being forced to unwind their positions. A rapid unwinding of these trades could further amplify market volatility.

Beyond Japan, this potential rate hike may become one of the most influential global financial events at year’s end. With an estimated USD 1–3 trillion in global yen carry trades at risk, a widespread unwinding could drive the yen sharply higher while simultaneously triggering sell-offs in U.S. Treasury bonds, technology stocks, and various emerging-market assets. With the U.S. Federal Reserve under increasing pressure to cut interest rates during 2025, a narrowing U.S.–Japan interest rate gap could add yet more volatility across global markets.

Current market estimates place the probability of a December rate hike at 76%, and policymakers may raise the policy rate from 0.5% to 0.75%. However, Japan’s public debt—which exceeds 230% of GDP—means that aggressive or rapid tightening would significantly increase government interest payments. As a result, markets widely expect the Bank of Japan to adopt a cautious and gradual approach even if it proceeds with hiking rates.

Despite the growing expectation of a rate hike, analysts remain divided on whether such a move can fundamentally reverse the yen’s long-term weakening trend. Some argue that Japan’s structural weaknesses remain unresolved, making it unlikely that mild rate hikes alone can sustain a stronger yen; on the contrary, the yen might resume its decline after a brief rebound. Others believe that if the Federal Reserve enters a rate-cutting cycle while Japan raises rates, the narrowing interest rate differential could trigger a meaningful yen appreciation, potentially reversing the depreciation trend observed in recent years. Even so, the uncertainty surrounding policy timing and shifting market expectations may lead to continued volatility.

Overall, the Bank of Japan’s signal of an impending rate increase represents not only a major pivot in Japan’s monetary policy but also one of the most closely watched developments in global financial markets. Regardless of whether the rate hike is ultimately implemented, the episode highlights Japan’s delicate balancing act between inflation, currency stability, and a massive debt burden. The outcome of this policy transition will likely have profound implications for both Asian and global financial markets in the months ahead.