President Reagan is welcoming the news that the nation's median income rose between 1986 and 1987, but analysts see the rich getting richer and a disappointing inability of economic recovery to end poverty.

According to an annual Census Bureau report, median family income grew to $30,850 last year, a 1 percent jump from 1986, but the poverty rate did not change significantly - with 32.5 million people, about 40 percent children, still mired in impoverishment.In California, where Reagan is on vacation, his spokesman accentuated the positive in Wednesday's report. Marlin Fitzwater acknowledged the "obviously disappointing" disparity in the income of blacks and whites but said, "The growing economy has indeed lifted the standard of living for everyone."

Likewise, Kate Walsh O'Beirne of the conservative Heritage Foundation in Washington called the report "excellent news."

"Thanks to strong economic growth since 1983, American families have fully recovered the ground they lost during the economic stagnation and double-digit inflation of the late 1970s," she asserted.

But Robert Greenstein of the liberal Center on Budget and Policy Priorities joined others who saw things differently, calling the news "disappointing."

"These data show that the economic recovery increasingly is leaving the poor behind," Greenstein said. "While unemployment rates have returned to the (low) levels of 1978, poverty levels are far higher with 8 million more Americans in poverty than in 1978."

In general, the government figures show the rich getting richer, the poor getting poorer, middle-income Americans losing ground and poverty spreading among blacks while shrinking among whites.

For example, the Census Bureau said that in 1987, the 20 percent of the population at the bottom of the financial barrel got only 4.6 percent of the aggregate family income, down from 4.7 percent in 1982. The wealthiest 20 percent, meanwhile, saw their share of family income jump a full percentage point, from 42.7 percent in 1982 to 43.7 percent in 1987.

By way of comparison, the poorest one-fifth of American families had a 5.5 percent share of the economic pie in 1967 while the richest one-fifth took home 40.4 percent.

Among the middle 60 percent, the 1987 share of aggregate family income was 51.7 percent, down from 52.6 percent in 1982. In 1967, the large middle group had a 54.1 percent share.

The median income is the figure above or below which there are equal numbers of families. The statistics are the most current available.

In another closely watched figure, the report said the ratio of female to male earnings in 1987 was 0.65, meaning a woman made 65 cents for every $1 earned by a man. That ratio is unchanged for the last three years. The 1987 median income of men was $26,010 and $16,910 for women.

The report said the number of people in poverty increased slightly between 1986 and 1987 even though the poverty rate, at 13.5 percent, did not differ statistically from its 1986 level of 13.6 percent.

The total number of people below the official poverty line - $11,611 for a family of four - was 32.5 million in 1987 compared with 32.4 million in 1986.

"The poverty rate for whites decreased between 1986 and 1987 while that for blacks increased."