''Kukurantumi: the Road to Accra,'' a co-production of Ghana and West Germany, is a comparatively lively, good-humored film about a very sad subject - the breakdown of family relationships under the pressures of what's called progress. The film is the first feature to be directed by King Ampaw, a Ghana film maker trained in West Germany and Austria and now a director with the Ghana Broadcasting Corporation.

The screenplay, by Mr. Ampaw and two German writers, is about Addey, a hard-working family man who makes his living driving a lorry between Accra, the capital, and his small village of Kukurantumi, which, in a local dialect, means ''the place where everything is too heavy to pick up.'' When he is dismissed from his job for reasons beyond his control, Addey arranges a marriage between his pretty daughter, Abena, and a rich, middle-aged businessman she doesn't love. Abena rebels and, with Bob, the poor young man she loves, runs off to Accra where things go from bad to worse.

Though its story is not a happy one, the film contains a good deal of rambunctious humor. The performances are awkward but also refreshingly straightforward, without guile.

''Kukurantumi'' will be shown at the 57th Street Playhouse today at 6 P.M. and tomorrow at 8:30 P.M., as part of the New Directors/New Films series sponsored by the Lincoln Center Film Society and the Museum of Modern Art's Department of Film.

The Cast KUKURANTUMI: THE ROAD TO ACCRA, directed by King Ampaw; written by King Ampaw, Ralf Franz and Thilo Kline; cinematography by Eckhard Dorn; edited by Anja Cox; produced by Peter Wohlgemuth-Reinery; a Reinery Verlag & Filmproduktion in association with Afro Movies Ltd. and North German Television; presented by The Film Society of Lincoln Center and The Department of Film of the Museum of Modern Art. At the 57th Street Playhouse, between Avenue of the Americas and Seventh Avenue. Running time: 83 minutes. This film has no rating. AddeyEvans Oma Hunter AbenaAmy Oppiah BobDavid Dontoh MaryDorothy Ankomah MensahGeorge Wilson KofiErnest Youngman SeewaaRose Flynn BoafoFelix Asant Larbi AlhajiKwesi France Old ManEmmi L. Lawson