The cv2.putText don't support no-ascii char in my knowledge. Try to use PIL to draw NO-ASCII(such Chinese) on the image.

import numpy as npfrom PIL import ImageFont, ImageDraw, Imageimport cv2import time## Make canvas and set the colorimg = np.zeros((200,400,3),np.uint8)b,g,r,a = 0,255,0,0## Use cv2.FONT_HERSHEY_XXX to write English.text = time.strftime("%Y/%m/%d %H:%M:%S %Z", time.localtime()) cv2.putText(img,  text, (50,50), cv2.FONT_HERSHEY_SIMPLEX, 0.7, (b,g,r), 1, cv2.LINE_AA)## Use simsum.ttc to write Chinese.fontpath = "./simsun.ttc" # <== 这里是宋体路径 font = ImageFont.truetype(fontpath, 32)img_pil = Image.fromarray(img)draw = ImageDraw.Draw(img_pil)draw.text((50, 80),  "端午节就要到了。。。", font = font, fill = (b, g, r, a))img = np.array(img_pil)cv2.putText(img,  "--- by Silencer", (200,150), cv2.FONT_HERSHEY_SIMPLEX, 0.5, (b,g,r), 1, cv2.LINE_AA)## Display cv2.imshow("res", img);cv2.waitKey();cv2.destroyAllWindows()#cv2.imwrite("res.png", img)

Refer to my another answer:

Load TrueType Font to OpenCV

According to this opencv forum, putText is only able to support a small ascii subset of characters and does not support unicode characters which are other symboles like chinese and arabic characters.

However, you can try to use PIL instead and follow the answer posted here and see if it works out for you.

Quick Start

np_img = np.ones((64, 32, 3), dtype=np.uint8) * 255  # background with white colordraw_text = init_parameters(cv2_img_add_text, text_size=32, text_rgb_color=(0, 0, 255), font='kaiu.ttf', replace=True)draw_text(np_img, '您', (0, 0))draw_text(np_img, '好', (0, 32))cv2.imshow('demo', np_img), cv2.waitKey(0)

what is init_parameters() and cv2_img_add_text()?

see as below:

EXAMPLE

from typing import Tupleimport numpy as npimport cv2from PIL import Image, ImageDraw, ImageFont# define decoratordef init_parameters(fun, **init_dict):    """    help you to set the parameters in one's habits    """    def job(*args, **option):        option.update(init_dict)        return fun(*args, **option)    return jobdef cv2_img_add_text(img, text, left_corner: Tuple[int, int],                     text_rgb_color=(255, 0, 0), text_size=24, font='mingliu.ttc', **option):    """    USAGE:        cv2_img_add_text(img, '中文', (0, 0), text_rgb_color=(0, 255, 0), text_size=12, font='mingliu.ttc')    """    pil_img = img    if isinstance(pil_img, np.ndarray):        pil_img = Image.fromarray(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))    draw = ImageDraw.Draw(pil_img)    font_text = ImageFont.truetype(font=font, size=text_size, encoding=option.get('encoding', 'utf-8'))    draw.text(left_corner, text, text_rgb_color, font=font_text)    cv2_img = cv2.cvtColor(np.asarray(pil_img), cv2.COLOR_RGB2BGR)    if option.get('replace'):        img[:] = cv2_img[:]        return None    return cv2_imgdef main():    np_img = np.ones(IMG_SHAPE, dtype=np.uint8) * 255  # background with white color    np_img = cv2_img_add_text(np_img, 'Hello\nWorld', (0, 0), text_rgb_color=(255, 0, 0), text_size=TEXT_SIZE)    np_img = cv2_img_add_text(np_img, '中文', (0, LINE_HEIGHT * 2), text_rgb_color=(0, 255, 0), text_size=TEXT_SIZE)    cur_y = LINE_HEIGHT * 3    draw_text = init_parameters(cv2_img_add_text, text_size=TEXT_SIZE, text_rgb_color=(0, 128, 255), font='kaiu.ttf', replace=True)    for msg in ('笑傲江湖', '滄海一聲笑'):        draw_text(np_img, msg, (0, cur_y))        cur_y += LINE_HEIGHT + 1    draw_text(np_img,              """123456789""", (0, cur_y))    cv2.imshow('demo', np_img), cv2.waitKey(0)if __name__ == '__main__':    IMG_HEIGHT, IMG_WIDTH, CHANNEL = IMG_SHAPE = (250, 160, 3)    TEXT_SIZE = LINE_HEIGHT = 32    main()